Based off a Billet Aluminum design where all others are of a less superior Forged design, ours are reinforced in all areas of concern and the strongest available on the market bar none!-Has an internal pocket radius in the GEN 2 design toward the rear of trigger which eliminated the back strap from breaking. Has a reinforced water line on our receiver, all others do not have this upgrades - They are impervious to gasoline, acid, acetone, kerosene, and will not break after being dunked in liquid nitrogen and thrown onto a concrete floor, unlike aluminum which would shatter! - These can handle up to 500 degrees, and in the summertime, they are not hot to touch like aluminum receivers! - They are lighter than aluminum and can be run over at the mag-well, where aluminum will be crushed and rendered useless! - If you scratch ours, they retain color and also a little WD-40, and some green scratch pad removes the scratch. - Our fire controls require no lubrication whatsoever - The castle nuts do not need to be torqued, or staked as they are factory torqued with blue Loctite, and will not come loose.