Pearce Grip Grip Extension For GLOCK 10mm/45acp 29/30/20/21/40/41 Matte Finish Black. This does not alter the capacity of the magazine. This unit works on all 10mm and 45ACP Magazines except 10 round Glock 30 magazines. Specifications for Pearce Grip Grip Extension For GLOCK 10mm/45acp 29/30/20/21/40/41 Matte Finish Black: Manufacturer: Pearce Grip Color: Black Finish: Black Additional Features: Magazine Base Plate Handle Color: Black Features of Pearce Grip Grip Extension For GLOCK 10mm/45acp 29/30/20/21/40/41 Matte Finish Black: Fits GLOCK 20/21/29/40/41/30 Magazines Package Contents: Pearce Grip Grip Extension For GLOCK 10mm/45acp 29/30/20/21/40/41 Matte Finish Black