Rubber-Cal 50A Durometer Neoprene Sheet 1/8 in. Thick x 2 in. Width x 36 in. Length Smooth Finish Black Rubber Sheet (0.5 sq. ft.) 30-005-125-002-036 - The Home Depot
Amazon.com: Small Parts 5NEO60-0500-12-12 Neoprene Sheet, 60A Durometer, Smooth Finish, No Backing, Black, 1/2" Thickness, 12" Width, 12" Length : Industrial & Scientific
Source neoprene Hardness 60 shore A rubber sheet on m.alibaba.com
Commercial Neoprene Sheeting 70° Shore - The Rubber Company