diff -u b/core/modules/breakpoint/breakpoint.module b/core/modules/breakpoint/breakpoint.module
--- b/core/modules/breakpoint/breakpoint.module
+++ b/core/modules/breakpoint/breakpoint.module
@@ -35,7 +35,7 @@
     if ($themes[$theme_key]->status) {
       $theme_breakpoints = breakpoint_get_theme_breakpoint_list($theme_key);
       if (!empty($theme_breakpoints)) {
-        if ($breakpoint_group = BreakpointGroup::loadFromTheme($theme_key, $themes[$theme_key]->info['name'], $theme_breakpoints)) {
+        if ($breakpoint_group = _breakpoint_import_breakpoints($themes[$theme_key]->info['name'], $theme_key, Breakpoint::SOURCE_TYPE_THEME, $theme_breakpoints)) {
           $breakpoint_group->save();
           $uri = $breakpoint_group->uri();
           if ($uri) {
@@ -85,7 +85,7 @@
   foreach ($modules as $module) {
     $module_breakpoints = breakpoint_get_module_breakpoint_list($module);
     if (!empty($module_breakpoints)) {
-      if ($breakpoint_group = BreakpointGroup::loadFromModule($module, $module, $module_breakpoints)) {
+      if ($breakpoint_group = _breakpoint_import_breakpoints($module, $module, Breakpoint::SOURCE_TYPE_MODULE, $module_breakpoints)) {
         $breakpoint_group->save();
         $uri = $breakpoint_group->uri();
         if ($uri) {
@@ -123,6 +123,68 @@
 }
 
 /**
+ * Import breakpoints from theme or module.
+ *
+ * @param string $label
+ *   Name of the breakpoint group.
+ * @param string $id
+ *   Id of the breakpoint group.
+ * @param string $sourceType
+ *   Either Breakpoint::SOURCE_TYPE_THEME or Breakpoint::SOURCE_TYPE_MODULE.
+ * @param array $media_queries
+ *   Array of media queries keyed by id.
+ *
+ * @return Drupal\breakpoint\BreakpointGroup|false
+ *   Returns the new breakpoint group if one is created.
+ */
+function _breakpoint_import_breakpoints($label, $id, $source_type, $media_queries) {
+  if (!empty($media_queries)) {
+    $weight = 0;
+    // Use the existing breakpoint group if it exists.
+    $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $id);
+    if (!$breakpoint_group) {
+      // Build a new breakpoint group.
+      $breakpoint_group = entity_create('breakpoint_group', array(
+        'id' => $id,
+        'label' => $label,
+        'source' => $id,
+        'sourceType' => $source_type,
+      ));
+    }
+    else {
+      // Reset label.
+      $breakpoint_group->label = $label;
+    }
+    foreach ($media_queries as $name => $media_query) {
+      // Use the existing breakpoint if it exists.
+      $breakpoint = entity_load('breakpoint', $source_type . '.' . $id . '.' . $name);
+      if (!$breakpoint) {
+        // Build a new breakpoint.
+        $breakpoint = entity_create('breakpoint', array(
+          'name' => $name,
+          'label' => drupal_ucfirst($name),
+          'mediaQuery' => $media_query,
+          'source' => $id,
+          'sourceType' => $source_type,
+          'weight' => $weight++,
+        ));
+        $breakpoint->save();
+      }
+      else {
+        // Reset name, label, weight and media query.
+        $breakpoint->name = $name;
+        $breakpoint->label = drupal_ucfirst($name);
+        $breakpoint->mediaQuery = $media_query;
+        $breakpoint->weight = $weight++;
+      }
+      $breakpoint_group->breakpoints[$breakpoint->id()] = $breakpoint;
+    }
+    return $breakpoint_group;
+  }
+  return FALSE;
+}
+
+/**
  * Import breakpoint groups from theme or module.
  *
  * @param string $group_id
@@ -132,14 +194,58 @@
  *
  * @return boolean
  */
-function _breakpoint_import_breakpoint_groups($source, $source_type) {
-  $breakpoint_groups = config($source . '.breakpoint_groups');
+function _breakpoint_import_breakpoint_groups($group_id, $source_type) {
+  $breakpoint_groups = config($group_id . '.breakpoint_groups');
   if ($breakpoint_groups) {
     foreach ($breakpoint_groups->get() as $id => $data) {
       // Breakpoints is mandatory.
       if (isset($data['breakpoints']) && !empty($data['breakpoints'])) {
-        if ($breakpoint_group = BreakpointGroup::ImportBreakpointGroup($source, $source_type, $id, isset($data['label']) ? $data['label'] : drupal_ucfirst($data[$id]), $data['breakpoints'])) {
-          $breakpoint_group->save();
+        // Use the existing breakpoint group if it exists.
+        $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $id);
+        if (!$breakpoint_group) {
+          $breakpoint_group = entity_create('breakpoint_group', array(
+            'id' => $id,
+            'label' => isset($data['label']) ? $data['label'] : drupal_ucfirst($data[$id]),
+            'source' => $group_id,
+            'sourceType' => $source_type,
+          ));
+        }
+        else {
+          // Reset label.
+          $breakpoint_group->label = isset($data['label']) ? $data['label'] : drupal_ucfirst($data[$id]);
+        }
+        foreach ($data['breakpoints'] as $breakpoint_id => $multipliers) {
+          // Check if breakpoint exists, assume short name.
+          $breakpoint = entity_load('breakpoint', $source_type . '.' . $group_id . '.' . $breakpoint_id);
+          // If the breakpoint doesn't exist, try using the full name.
+          if (!$breakpoint) {
+            $breakpoint = entity_load('breakpoint', $breakpoint_id);
+          }
+          if ($breakpoint) {
+            // Check if the multipliers are set, if not set them now.
+            if (is_array($multipliers) && !empty($multipliers)) {
+              // Check settings first.
+              $settings = breakpoint_settings();
+              $defined_multipliers = $settings->multipliers;
+              $new_multipliers = array_diff($multipliers, $defined_multipliers);
+              if (!empty($new_multipliers)) {
+                $defined_multipliers = array_merge($defined_multipliers, $new_multipliers);
+                breakpoint_settings_save_multipliers($defined_multipliers);
+              }
+
+              // Check breakpoint multipliers.
+              $multipliers = drupal_map_assoc(array_values($multipliers));
+              $new_multipliers = array_diff($multipliers, $breakpoint->multipliers);
+              if (!empty($new_multipliers)) {
+                $breakpoint->multipliers += $new_multipliers;
+                $breakpoint->save();
+              }
+            }
+
+            // Add breakpoint to group.
+            $breakpoint_group->breakpoints[$breakpoint->id()] = $breakpoint;
+            $breakpoint_group->save();
+          }
         }
       }
     }
@@ -178,7 +284,7 @@
       }
     }
   }
-  // Delete groups defined by a module/theme even if that module/theme didn't
+  // Deletet groups defined by a module/theme even if that module/theme didn't
   // define any breakpoints.
   foreach ($ids as $id) {
     // delete all breakpoint groups defined by the theme or module.
@@ -248,7 +354,7 @@
   if (isset($themes[$theme_key]) && $themes[$theme_key]->status) {
     $theme_breakpoints = breakpoint_get_theme_breakpoint_list($theme_key);
     if (!empty($theme_breakpoints)) {
-      return BreakpointGroup::loadFromTheme($theme_key, $themes[$theme_key]->info['name'], $theme_breakpoints);
+      return _breakpoint_import_breakpoints($themes[$theme_key]->info['name'], $theme_key, Breakpoint::SOURCE_TYPE_THEME, $theme_breakpoints);
     }
   }
   return FALSE;
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/Breakpoint.php b/core/modules/breakpoint/lib/Drupal/breakpoint/Breakpoint.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/Breakpoint.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Breakpoint.php
@@ -116,6 +116,10 @@
    */
   public function __construct(array $values = array(), $entity_type = 'breakpoint') {
     parent::__construct($values, $entity_type);
+    if (!isset($this->uuid)) {
+      $uuid = new Uuid();
+      $this->uuid = $uuid->generate();
+    }
   }
 
   /**
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/BreakpointGroup.php
@@ -78,6 +78,11 @@
    */
   public function __construct(array $values = array(), $entity_type = 'breakpoint_group') {
     parent::__construct($values, $entity_type);
+    // Assign a new UUID if there is none yet.
+    if (!isset($this->uuid)) {
+      $uuid = new Uuid();
+      $this->uuid = $uuid->generate();
+    }
     $this->loadAllBreakpoints();
   }
 
@@ -159,164 +164,6 @@
   }
 
   /**
-   * Add a breakpoint using a name and a media query.
-   *
-   * @param string $name
-   *   The name of the breakpoint.
-   * @param string $media_query
-   *   Media query.
-   */
-  public function addBreakpointFromMediaQuery($name, $media_query) {
-    // Use the existing breakpoint if it exists.
-    $breakpoint = entity_load('breakpoint', $this->sourceType . '.' . $this->id . '.' . $name);
-    if (!$breakpoint) {
-      // Build a new breakpoint.
-      $breakpoint = entity_create('breakpoint', array(
-        'name' => $name,
-        'label' => drupal_ucfirst($name),
-        'mediaQuery' => $media_query,
-        'source' => $this->id,
-        'sourceType' => $this->sourceType,
-        'weight' => count($this->breakpoints),
-      ));
-      $breakpoint->save();
-    }
-    else {
-      // Reset name, label, weight and media query.
-      $breakpoint->name = $name;
-      $breakpoint->label = drupal_ucfirst($name);
-      $breakpoint->mediaQuery = $media_query;
-      $breakpoint->weight = count($this->breakpoints);
-    }
-    $this->breakpoints[$breakpoint->id()] = $breakpoint;
-  }
-
-  /**
-   * Load breakpoints from a theme and build a default group.
-   *
-   * @param string $theme_key
-   *   The name of the theme.
-   * @param string $name
-   *   The human readable name of the theme.
-   * @param array $media_queries
-   *   Array of media queries keyed by id.
-   *
-   * @return \Drupal\breakpoint\BreakpointGroup|false
-   *   Return the new breakpoint group containing all breakpoints.
-   */
-  public static function loadFromTheme($theme_key, $name, $media_queries) {
-    return BreakpointGroup::loadFromThemeOrModule($theme_key, $name, Breakpoint::SOURCE_TYPE_THEME, $media_queries);
-  }
-
-  /**
-   * Load breakpoints from a module and build a default group.
-   *
-   * @param string $module
-   *   The name of the theme.
-   * @param string $name
-   *   The human readable name of the module.
-   * @param array $media_queries
-   *   Array of media queries keyed by id.
-   *
-   * @return \Drupal\breakpoint\BreakpointGroup|false
-   *   Return the new breakpoint group containing all breakpoints.
-   */
-  public static function loadFromModule($module, $name, $media_queries) {
-    return BreakpointGroup::loadFromThemeOrModule($module, $name, Breakpoint::SOURCE_TYPE_MODULE, $media_queries);
-  }
-
-  /**
-   * Load breakpoints from a theme/module and build a default group.
-   *
-   * @param string $id
-   *   Name of the breakpoint group.
-   * @param string $label
-   *   Human readable name of the breakpoint group.
-   * @param string $sourceType
-   *   Either Breakpoint::SOURCE_TYPE_THEME or Breakpoint::SOURCE_TYPE_MODULE.
-   * @param array $media_queries
-   *   Array of media queries keyed by id.
-   *
-   * @return \Drupal\breakpoint\BreakpointGroup|false
-   *   Return the new breakpoint group containing all breakpoints.
-   *
-   * @see Drupal\breakpoint\BreakpointGroup::loadFromTheme()
-   * @see Drupal\breakpoint\BreakpointGroup::loadFromModule()
-   */
-  protected static function loadFromThemeOrModule($id, $label, $source_type, $media_queries) {
-    $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $id);
-    /* @var $breakpoint_group \Drupal\breakpoint\BreakpointGroup */
-    if (!$breakpoint_group) {
-      // Build a new breakpoint group.
-      $breakpoint_group = entity_create('breakpoint_group', array(
-        'id' => $id,
-        'label' => $label,
-        'source' => $id,
-        'sourceType' => $source_type,
-      ));
-    }
-    else {
-      // Reset label.
-      $breakpoint_group->label = $label;
-    }
-
-    foreach ($media_queries as $name => $media_query) {
-      $breakpoint_group->addBreakpointFromMediaQuery($name, $media_query);
-    }
-    return $breakpoint_group;
-  }
-
-  /**
-   * Import breakpoint groups from theme or module.
-   *
-   * @param string $source
-   *   Source of the breakpoint group, theme_key or module name.
-   * @param string $sourceType
-   *   Either Breakpoint::SOURCE_TYPE_THEME or Breakpoint::SOURCE_TYPE_MODULE.
-   * @param string $name
-   *   Name of the breakpoint group.
-   * @param string $label
-   *   Human readable name of the breakpoint group.
-   * @param array $breakpoints
-   *   Array of breakpoints, using either the short name or the full name.
-   *
-   * @return \Drupal\breakpoint\BreakpointGroup|false
-   *   Return the new breakpoint group containing all breakpoints.
-   */
-  public static function ImportBreakpointGroup($source, $source_type, $name, $label, $breakpoints) {
-    // Use the existing breakpoint group if it exists.
-    $breakpoint_group = entity_load('breakpoint_group', $source_type . '.' . $name);
-    /* @var $breakpoint_group \Drupal\breakpoint\BreakpointGroup */
-    if (!$breakpoint_group) {
-      $breakpoint_group = entity_create('breakpoint_group', array(
-        'id' => $name,
-        'label' => !empty($label) ? $label : $name,
-        'source' => $source,
-        'sourceType' => $source_type,
-      ));
-    }
-    else {
-      // Reset label.
-      $breakpoint_group->label = !empty($label) ? $label : $name;
-    }
-
-    // Add breakpoints to the group.
-    foreach ($breakpoints as $breakpoint_name) {
-      // Check if breakpoint exists, assume short name.
-      $breakpoint = entity_load('breakpoint', $source_type . '.' . $source . '.' . $breakpoint_name);
-      // If the breakpoint doesn't exist, try using the full name.
-      if (!$breakpoint) {
-        $breakpoint = entity_load('breakpoint', $breakpoint_name);
-      }
-      if ($breakpoint) {
-        // Add breakpoint to group.
-        $breakpoint_group->breakpoints[$breakpoint->id()] = $breakpoint;
-      }
-    }
-    return $breakpoint_group;
-  }
-
-  /**
    * Load all breakpoints, remove non-existing ones.
    */
   protected function loadAllBreakpoints() {
diff -u b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointThemeTest.php b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointThemeTest.php
--- b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointThemeTest.php
+++ b/core/modules/breakpoint/lib/Drupal/breakpoint/Tests/BreakpointThemeTest.php
@@ -134,13 +134,24 @@
     ));
     $breakpoint_group_obj->breakpoints = array(
       'theme.breakpoint_test_theme.mobile' => array(),
-      'theme.breakpoint_test_theme.narrow' => array(),
+      'theme.breakpoint_test_theme.narrow' => array('3.x', '4.x'),
       'theme.breakpoint_test_theme.wide' => array(),
     );
 
     // Verify we can load this breakpoint defined by the theme.
     $this->verifyBreakpointGroup($breakpoint_group_obj);
 
+    // Check that the multipliers are added to the settings.
+    $settings = breakpoint_settings();
+    $expected_settings = array(
+      0 => '1x',
+      1 => '1.5x',
+      2 => '2x',
+      3 => '3x',
+      4 => '4x',
+    );
+    $this->assertEqual($settings->multipliers, $expected_settings, 'Multipliers are added to settings.');
+
     // Disable the test theme and verify the breakpoint group still exists.
     theme_disable(array('breakpoint_test_theme'));
     $this->assertTrue(entity_load('breakpoint_group', 'module_test'), 'Breakpoint group still exists if theme is disabled.');
diff -u b/core/modules/breakpoint/tests/config/breakpoint_theme_test.breakpoint_groups.yml b/core/modules/breakpoint/tests/config/breakpoint_theme_test.breakpoint_groups.yml
--- b/core/modules/breakpoint/tests/config/breakpoint_theme_test.breakpoint_groups.yml
+++ b/core/modules/breakpoint/tests/config/breakpoint_theme_test.breakpoint_groups.yml
@@ -4,3 +4,3 @@
-    - theme.breakpoint_test_theme.mobile
-    - theme.breakpoint_test_theme.narrow
-    - theme.breakpoint_test_theme.wide
+    theme.breakpoint_test_theme.mobile: []
+    theme.breakpoint_test_theme.narrow: ['3x', '4x']
+    theme.breakpoint_test_theme.wide:
diff -u b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/breakpoint_test_theme.info b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/breakpoint_test_theme.info
--- b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/breakpoint_test_theme.info
+++ b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/breakpoint_test_theme.info
@@ -5 +5 @@
-hidden = TRUE
+hidden = FALSE
diff -u b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/config/breakpoint_test_theme.breakpoint_groups.yml b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/config/breakpoint_test_theme.breakpoint_groups.yml
--- b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/config/breakpoint_test_theme.breakpoint_groups.yml
+++ b/core/modules/breakpoint/tests/themes/breakpoint_test_theme/config/breakpoint_test_theme.breakpoint_groups.yml
@@ -4,3 +4,3 @@
-    - mobile
-    - narrow
-    - wide
+    mobile: ['1.5x', '2x']
+    narrow:
+    wide: