RCM - Sig Sauer M400 / 516 Magwell Model:516 G3 For the Polymer APC45 lower

For the Polymer APC45 lower that uses steel B&T magazines select the Polymer B&T option

The SR25 RCM H (Rifle Combat Magwell Heavy) features a 250% larger flared funnel surface allowing for consistent and fast reloads under any condition and is designed for the KAC SR25 and M110 lowers

The Black Hills Designs RANGE-R card is the premier passive range finding solution

Compatible with all major magazines (including M3 PMAGs) on the market as well as higher capacity options like the Magpul D60 or Surefire MAG5-60

M400-TREAD and SIG 516 lowers

RCM - Sig Sauer M400 / 516 Magwell Model:516 G3 For the Polymer APC45 lowerRifle Combat Magwell for Sig Sauer M400 M400 SDI The Sig Sauer M400 RCM (Rifle Combat Magwell) features a 250% larger flared funnel surface allowing for consistent and fast reloads under any condition and is intended to fit the SIG M400, M400 PRO, M400 TREAD and SIG 516 lowers. The SDI model will fit on SIG M400 SDI, SDI X or DH3 models. The 516 G3 model will fit on the newer SIG 516 G3 lowers. THERE ARE MULTIPLE VARIATIONS OF LOWER RECEIVER UNDER THE