Seems like reasonable, logical, cheap insurance on an SBR lower...especially one that gets used.

Quote Originally Posted by docsherm View Post
They hold the pins in place for triggers that are actually used, as the lower wears out and the holes get bigger. I have an SBRed DPMS lower that is almost 20 years old and has over 55k through it. It is on its 4th trigger. It has KNS pins because when you actually use something it will wear out, no matter if it is an Anderson Arms lower or a Colt.

OP- what trigger are you using? The pins and the lower may be slightly off. That can cause some movement and additional wear on the parts.