Drywall Flat Box Wingnut Assembly for Handle Mounting Plate - Most Major Brands

Drywall Flat Box Wingnut Assembly for Handle Mounting Plate 

This screws into the pressure plate of your flat box and connects to your handle 

Works with most major brands

Tapetech - All Sizes and Models

Drywall Master - All Sizes and Models

Columbia -  All Sizes and Models

Level5 - Not a 1 to 1 fit but it works