This pin has a hemispherical end, for smooth, non-penetrating contact. Normally used for testing circuit boards or programming via electronic JTAG interfaces, they also make killer-looking robot feet!

This model has a round-tip 0.70mm (0.028") in diameter. The outer shaft diameter is 1.01mm (0.040"), overall uncompressed length of 33mm (1.3") with 6.5mm (1/4") travel.