SKB Cases Mil-Std Waterproof Case 7in. Deep (empty) 20-1/2 x 15-1/2 x 7-1/2 3I-2015-7B-E. The SKB 3I Series Injection Molded Mil-Standard Waterproof Cases are molded of ultra high-strength polypropylene copolymer resin featuring a gasketed water and...