Wilson Combat Anti-Walk, Trigger Pins, .154 Diameter, Fits AR Platforms, Black TR-AWP-B Anti-Walk locking pins replace your AR trigger and hammer pins to ensure pins do not rotate or vibrate loose out of the receiver. This is a popular" inexpensive and drop-in enhancement for tactical" hard-use guns. These pins are compatible with a standard USGI style AR style lower receiver with standard GI trigger pins of .154" diameter regardless of caliber" including 7.62/.308 length AR receivers.