Wheeler Pivot Pin Install Tool, For AR-15/M16, Black 156243 The Wheeler Delta Series AR Pivot & Roll Pin Installation Tool is designed for use with the AR-15" M4 or M-16 rifles. The Wheeler(R) AR Pivot Pin/Roll Pin Install tool makes pivot pin spring and detent work fast and effortless. It comes with handy key ring for storage" and is made of black zinc plated steel to stand up to any job.