Fits:

Glock 17, 17 L and 34 magazines of 17 and 19 rounds

Glock 20, 21, 22 , 31, 34 and 35 magazines of 15 rounds.

• Use of this spring may require a slightly higher power recoil spring to overcome the additional tension of the top cartridge pressing on the pistol’s slide.
• Also recommended when using extra power recoil springs.
• Installation requires disassembly and reassembly of the magazine.