form the skin coating the material can be selected to have for example good sealing characteristics for a particular application or to add puncture resistance to the product or to add toughness or stiffness to the product it is also possible for the coating to provide enhanced uv stability fire retardance or intense colour other applications include printable surface friction characteristics and adhesion characteristics these examples are not limiting and other characteristics can be achieved for a particular application the body portion can be a polyethylene enhanced material to provide good resiliency and a fairly firm body portion with respect to compression it is a relatively dense body portion and the size of the cells is small and consistent with this arrangement the main extruder u201c a u201d operates with the enhanced polyethylene material and can extrude product at a rate of about 50 pounds per hour the enhanced polyethylene material has a melting point in the range of 95 u00b0 c to 98 u00b0 c in contrast the surface material of extruder u201c b u201d can have a much higher melting point as the material exits the ring orifice 14 it is at a temperature of higher than the cooler body portion almost immediately after the coating is applied to the body portion the product exits the main die.