Abstract: A key switch includes a key base having a rectangular hole at the top, a conductive rubber cone received inside the key base at the bottom and supported on a circuit board, a plunger received in the rectangular hole and having a mounting slot at the top and two unitary spring strips extended from two opposite sides thereof and terminating in a respective hooked portion hooked on a respective retaining groove on the key base from the bottom, and a key cap having a hollow projecting rod fitted into the mounting slot on the plunger for permitting the plunger to be moved downward to trigger an electric contact on the circuit board through the conductive rubber cone upon each striking against the key cap.

Abstract: A key switch includes a rectangular key cap having a unitary, hollow, rectangular plunger inserted into a rectangular hole on a key base and pressed to squeeze a rubber tone causing a conductor to electrically connect a contact on the printed circuit board of a keyboard, wherein the rectangular plunger has four circular rails on the four corners thereof along its length respectively inserted in four circular grooves on the rectangular guide slot of the key base for stable movement, and two smoothly curved, hooked spring plates releasably hooked with two opposite hooked portions on the key base for positioning.