Two-piece, synthetic base pad increases the cartridge capacity of pre-ban, GlockA(R) magazines without compromising reliability. Impact-resistant pad locks securely to the magazine body; removes quickly and easily with the supplied compression tool. Wolff, 10% extra power spring ensures reliable feeding. Checkered, bottom panel allows positive, non-slip, mag changes. Plus 5 extends pre-ban magazines to 140mm. Adds +5 to 10 mm, and +4 to .45 ACP. USPSA Limited legal. Mfg: Arredondo