The Redi-Catch allows for the bolt to be locked open by pressing the
magazine catch with the trigger finger while pulling the bolt back with
the left hand. The result is a more ergonomic and rapid bolt lock back.
Installation is a breeze. Simply remove the existing magazine catch
and replace with the Redi-Catch. Then place one end of the "S" shaped
flexible spring steel wire in the Redi-Catch hole and making sure the
wire is in the groove near the top of the Redi-Catch post, place the
other end behind the bolt catch paddle.
Though the ABC/R (Augmented Bolt Catch/Release) was designed specifically for users with ambidextrous mag catch (which the Redi-Catch isn't), together, they offer superior ergonomics and new usability to the AR15 user.
Please note that with the Redi-Catch installed, the pressure required to press the magazine release button is increased (both the mag catch spring and bolt catch spring are being compressed), We do not consider it a negative or compromise in light of what Redi-Catch offers to the user.