Machined from a solid block of 7075 aluminum, LRF is an ambidextrous AR15 lower receiver with built-in right side bolt release, designed to use our EMR-A (Enhanced Magazine Release, Ambidextrous), a Norgon Ambi-Catch will also work on the LRF. LRF was designed with duty and defense users in mind. Its changes from TDP based lowers are based on ergonomics and better protection of magazine releases (both left and right side):LRF was designed with duty and defense users in mind. Its changes from TDP based lowers are based on ergonomics and better protection of magazine releases (both left and right side):* EMR-A (Enhanced Magazine Release, Ambidextrous) fence on the left side.* Taller than TDP spec magazine release fence on the right side to ensure TDP spec magazine release button stays below the fence.* Countersunk take down pin hole on the left, when the user pushes the take down pin in from the left side, the pin can be pushed in further, with more protrusion on the right to pull from. Flared magazine well with a larger opening.