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+Commerce Product Add On
+=================
+
+With Commerce Product Add On you can make product variations be offered for up-selling on another product's Add to cart form. 
+
+The way it works is by adding a product entity reference field to a product type. Selecting products A and B for product C will then make all variations of A and B appear in the Add to cart form of all product variations of C. 
+
+## Setup
+
+1. Install the module.
+
+2. Add a product entity reference field to your product type. 
+
+3. Go to the 'Manage display' tab of the product type.
+  * Select 'Add to cart form with add-ons' for the Variations field
+  * Configure the formatter settings of the Variations field and select your product entity reference field. 
+  * You probably want to hide your product entity reference field.
+  * Save the display.