... the circuit layer is made of PET (polyester)5) Key type: embossed key, poly dome, tactile6) Surface treatment: screen print, glossy ... : 3M, Sony, Soken, or any tape you choose3) Key type: flat key or embossed key, tactile or non-tactile, poly dome or metal ... membrane switches:1) Life Expectancy: 1,000,000 actuations per switch position2) Actuation Force: 6~24 ounces (170~680g), Range depending ...