Add two methods.

CSSSassCollectionMixins.scss

@@ -165,6 +165,14 @@
   }
 }
 
+@mixin Height ($Height) {
+  height: $Height !important;
+}
+
+@mixin Width ($Width) {
+  width: $Width !important;
+}
+
 @mixin BoxShadow ($Arguments) {
   -webkit-box-shadow: $Arguments;
   -moz-box-shadow: $Arguments;

test/_helper.spec.scss

@@ -16,6 +16,32 @@
     }
   }
 
+  @include it('check Height output') {
+    @include assert {
+      @include output {
+        @include Height(95%);
+        @include Height(95px);
+      }
+      @include expect {
+        height: 95% !important;
+        height: 95px !important;
+      }
+    }
+  }
+
+  @include it('check Width output') {
+    @include assert {
+      @include output {
+        @include Width(95%);
+        @include Width(95px);
+      }
+      @include expect {
+        width: 95% !important;
+        width: 95px !important;
+      }
+    }
+  }
+
   @include it('check BoxShadow output') {
     @include assert {
       $Arguments: 1px solid;