The Forward Control Designs AR-15 ABC/R (Augmented Bolt Catch/Release) with its angled and larger top paddle and lower paddle with increased surface area, is purpose designed for use with AR15/M16 receivers equipped with ambidextrous magazine releases. Specifically, it is designed to address the difficulty with accessing the factory bolt catch's lower paddle with an ambidextrous magazine catch, such as Norgon's Ambi-Catch, on the receiver. Many of the ambidextrous mag release's lower paddle is on the same vertical plane as the factory bolt catch lower paddle, making identification difficult by feel, especially with a gloved hand. The ABC/R's chief effort is focused on that single issue. The lower paddle protrudes further and is angled at 10 degree to give it even more surface area. These measures put the lower paddle and Ambi-Catch's paddle on different vertical planes. That done, they worked on the top paddle. While while FCD doesn't use it themselves, preferring to pull back on the charging handle instead to load and reload, they do recognize far more users use it, so the ABC/R's top paddle is made larger, and given a 5 degree angle at the lower 50%, and 10 degree angle at the upper 50% cant. The angled paddle makes it easier for the palm or thumb to access. The notch immediately above the ABC/R’s lower paddle is not there by accident. As you run your finger down the bolt catch towards the lower paddle, the notch is meant to provide tactile feedback to indicate the beginning of the lower paddle. It is important be able to differentiate one control surface from another, all without diverting one's gaze to it. ABC/R v3 upper paddle options accommodate individual user's reloading technique. Upper paddle options include FB (forward biased), standard (centered, non-biased), and RB (rearward biased). FB (forward biased) is for right hand users that wrap their left hand around the magazine well and use their left thumb to press the bolt catch's upper paddle. The FB version has the upper paddle shifted to the muzzle end to facilitate this reloading method. Standard (non-biased) upper paddle remains the same position as v1 and v2 ABC/R, its upper paddle isn't biased towards the front or rear. RB (rearward biased) is for left hand users that use their extended left index finger to access the bolt catch paddles. The RB version has the upper paddle shifted to the butt stock end to make the upper paddle more accessible. The ""butterfly"" lower paddle's horizontal extension increases the lower paddle's surface area, but stops short of reaching the bottom of the bolt catch in order to create a standoff distance between the extension and an ambidextrous magazine catch's lever. It is their opinion and observation that close proximity of two control surfaces is best avoided. The butterfly lower paddle has increased surface area and doesn't interfere with an ambidextrous mag catch's lever. Machined from billet 8620 alloy steel and heat treated with a DLC coating. The ABC/R v3 is proudly designed and made in the USA. Starting from June 15, 2018, bolt catch roll pin, plunger and spring are included. Starting from June 15, 2018, bolt catch roll pin, plunger and spring are included.