F.A.B. Defense Magazine Extension, Floor-Plate, 43-10 Adds 4 Rounds, For The Glock 43, Black Finish FX-4310B The 43-10 is a magazine floor-plate replacement for the Glock 43 that adds 4 rounds for a total of 10 rounds in a magazine. Special ergonomic design enables secure manipulation of the magazine and a full grip on the weapon when the magazine is in use.