The SC APC fibre optic adapter is the standard adapter for SC APC connectors. Developed by NTT Japan, the SC connector has a rectangular housing with the same dimensions of the pins and coupling sleeve as the FC type. The end face of the pins are mostly ground APC type; the fastening method is plug-in and plug-out, no rotation is required. These connectors are inexpensive, easy to plug and unplug, have low insertion loss fluctuations, high compressive strength and high installation density.