The RackGold Black Snap Cage nuts snap into square hole rack rails, giving you various threading options such as 10-32, 12-24, M5 or M6. Dell servers typically use 10-32 style threading, Compaq most often use M6 threads. Most telco 2-post relay racks use 12-24 threads. The nut is housed within a 3/8 inch spring metal body. When each side tab on the body is compressed, the nut can be inserted into the square hole in the rack rail. Most often used for mounting of servers, rack shelves, switches, routers, and other networking, electronic and data equipment. Mfr # GM5-SNP-B50