Pearce Grip Mag Extension - Fits Ber92, Brng HP, & Sig P228/P229, Black

These fit on CZ pistol magazines just fine. Omit the inner spring cage, and trim the follower as needed in order to reliably feed in and out of the extension. I was able to make 15+1 in 40sw and others have reported as many as 23+1 in sp-01 magazines for 9mm. Your mileage may vary. I have not figured a way to retain the base to the magazine tube to keep it from sliding foward - however, when a magazine is fully loaded, the extension isn''t going anywhere. I shoot these extensions as 15+1 with a CZ-40b in USPSA Limited Division.