Shield Arms S15 +0 Aluminum Magazine Base Plate - Black - Aluminum +0 replacement base plate for the S15 magazine. Shield Arms' aluminum base plate features a more aggressive design with three cut outs for improved grip - one on either side, and one on the front. The bottom of the base plate features a bigger dot matrix for more markup options. Machined From Billet Aluminum 3 Window Cuts For Increased Grip Slightly Taller Than OEM Plastic Base Plate Fits Gen 1 And Gen 2 (Ambi) S15 Magazines Only Made In The USA 100% Lifetime Warranty