An ethylene copolymer composition comprising an ethylene\u03b1-olefin copolymer, A-4, of ethylene with an \u03b1-olefin of 3 to 20 carbon atoms in an amount of 65-98% by weight, whose melt tension, MT, at 190\xb0 C. In certain embodiments, tubes inserted within the manifold adjacent to a refrigerant inlet have non-rectangular or recessed end profiles configured to increase flow area near the inlet, thereby reducing a pressure drop through the manifold. The lock is movable between hold and release positions to accommodate replacing of the wear member when needed, and secured to the wear member for shipping and storage purposes. The processor determines a change in thermal temperature sensed by the infrared detector and determines the presence of an object in the coverage zone based on the change in the sensed temperature. Characters and other selectable inputs corresponding to knob positions can be varied by the computer in the machine to reduce the risk of a criminal intercepting the user’s inputs to the machine.