I'm not an expert on this but the grey minicell is a stiff carve able type of mini cell foam. There are many mini cell foams some are used as cushions and are rubbery and not as easy to carve as the grey we all know. So before you send away, call them and tell them that you want the same viscosity as the grey stuff that kayak stores sell for carving things. There's a serial number for the grey stuff which identifies it as a certain elasticity and characteristics that it is. When I see a web site offering various colors, the red flag goes up because I made that mistake myself. The term mini cell just means it won't absorb water.