Rise Armament Super Sporting Trigger, Live Free or Die, Flat Trigger, Anodized Finish, Black and White, Includes Anti-Walk Pins RA-140F-LFOD-AWP There are many vital components in an AR. Items like bolt-carrier groups" upper receivers" and handguards all play a role. They come together to form one of the most popular firearm platforms in the U.S. But of all the parts and pieces" only one offers a direct interface between the gun and you: The trigger. This unsung hero sitting inside the lower receiver is the start of every fired shot.