... early 1980.1)Items——membrane switch, keypad, membrane keypad, keyboard switch, switch panel, membrane panel, membrane overlay, membrane faceplate ... for variety electronic industries. 2) Material——available in Polyester (PET) or Polycarbonate (PC).In ... or lessf) Actuation forcef-1) Flat type 60 - 300g (2 - 10oz)f-2) Tactile type——150 - 400g (6 - 14oz.)g) ...