Office Chair Arm Pad Replacement Part Armrest Caps Tops. Pad is of medium density with a slight concave surface. It is slightly curved so that it corresponds to the natural position when typing. Price per set of 2 pcs and includes 4 mounting screws. Pads are 9.25" long x 3.25" wide. Undercut is 5 7/8" long x 1 7/8" wide.