We recommend this one over part # SPF4857K (without the -90K at the end).  The normal one is too soft and has given some clients issues.  Get this one instead. The base material used by...

Do NOT buy this!  Its too soft and will break.  Purchase instead the part # SPF4857K-90K. The base material used by SuperPro is a polyurethane elastomer;a class of “Thermosetting” synthetic...

The base material used by SuperPro is a polyurethane elastomer;a class of “Thermosetting” synthetic polymer that involves the reaction of various types of isocyanate resins with curing agents, to...