Les Baer magazines incorporate the best stainless steel, lip, and follower design for trouble-free reliability. Magazine tubes are electro-polished inside and out for smooth function. Base plates are removable for easy cleaning. Notes:If the grips on your 1911 measure 4" long, you have a Government/Commander length grip. If the grips on your 1911 measure 3-1/2" long, you have an Officer/Defender length grip.