The SLIC Pin is a new quick locking pin that functions as a pin and a cotter all in one. SLIC is an acronym for Self Locking Implanted Cotter, and as the name implies, the pin is secure and self locking through the use of an implanted plunger that effectively functions as a self-contained cotter pin. The pin features a solid, spring loaded “wedge shaped plunger” that combines ease of use with secure fastening. The wedge shaped plunger easily and automatically retracts when the pin is inserted into a hole. The angled, ramp-like face of the wedge ensures smooth insertion. The SLIC Pin is intended for use as a semi-permanent quick locking pin and can be used in a multitude of applications. It replaces other labor intensive fastening combinations such as a clevis pin and cotter pin, a pin and retaining ring, or a nut and bolt. It is used in the same manner, but has much improved functionality and ease of assembly. The simple, one-piece design means easier, safer, and faster assembly speeds. No tools are needed and there are no sharp ends as with cotter pins. The SLIC Pin can be configured to suit individual applications. It can be produced in a Clevis Pin head style, grab ring style or others styles.