These AR15 anti walk / anti rotation hammer and trigger pins are what you need to keep your receiver from excessive wear and tear. Keeping the hammer and trigger pins from rotating is especially important when shooting full auto or with pistol caliber builds, such as 9mm AR15's.
Elftmann Non-Rotating Anti-walk Trigger and Hammer Pins - Arm or Ally
AR Triggers & Anti-Rotation Trigger Pins - School of the American Rifle - AR Build Junkie
AR Lower Parts - AR10 & AR15 Lower Parts
Strike Industries Anti-walk/Anti-rotation Trigger/Hammer Pins
AR-15 / AR-10 SAVAGE STAINLESS CERAKOTE Anti Walk Hammer Trigger Pins
A1Armory AR-15 Anodized Orange Anti-Rotation Trigger/Hammer Pin Set
KNS Precision AR-15/M16/AR10 Gen ST Non-Rotate Trigger/Hammer Pins
KNS Anti-Walk Hammer Trigger Pin Gen ST Non Rotating AR-15, LR-308
AR Triggers & Anti-Rotation Trigger Pins - School of the American Rifle - AR Build Junkie
Tacfire MAR108 AR15 ANTI-WALK PIN SET 33% Off 4 Star Rating Free Shipping over $49!
Strike Industries Anti-walk/Anti-rotation Trigger/Hammer Pins
AR-15/AR-10 Parts and Accessories - AR-15 Non-Rotating Trigger/Hammer Pin Sets - Page 1 - KNS Precision Inc.
PIN SET, AR PLATFORM, HAMMER/TRIGGER, ANTI-WALK, BLACK