US Patent 9532633 Protective cover with lock-in design

The present invention is a cover system for a device that includes a base with outer and inner surfaces. The outer surface includes a plurality of polygonal recesses, each having a bottom and a plurality of side walls with wall surfaces. Each one of the polygonal recesses has at least one wall in common with at least one other recess. The invention also includes one or more polygonal inserts with, each polygonal insert having a cap with two sides and a first stem extending from one side of the cap. The stem is shaped to form a friction fit when inserted into a recess. Some stems may include an o-ring that fits into a groove extending along all wall surface of a recess.