The Dead Foot Arms SCW rifle stock is by far the shortest AR-9 PDW style stock available for the AR-9 / PCC platform. Compatible with most all AR-9's (Glock, Colt, Endomag and MP5/MP9 magazines) including the Angstadt Arms UDP-9 and 0940 receivers. The MCS stands for modified cycle system because Dead Foot Arms has shortened the stock on a traditional AR-9 system from 7" to just 2.5". This is the shortest AR-9 rifle stock available. If you want the smallest 9MM PDW stock, the Dead Foot Arms SCW is it! The 9MM Gen 2 SCW 2.5 stock features an ergonomic design that uses dual rails that are offset to not interfere with weapon controls or function. While compact, it is still very versatile, allowing for button free stock deployment and 6 length of pull settings. At full extension, length of pull (LOP) reaches 12.6", keeping it comfortable for shooters of all sizes. SCW Stock Gen 2 upgraded features: Left-handed cheek rest Dual anti-rotation QD Mounts Hard stop at last LOP (length of pull) Dual rails for added stability This is a complete 9MM short stock conversion kit including: Complete SCW stock assembly 9MM MCS Bolt Carrier Group with black nitride finish Receiver extension and adjustment rail Plunger, spring cap, recoil/plunger springs and rubber bumper for 9mm System weight, excluding BCG is 17 oz Shortened 9MM BCG - Materials & Features: Shortened 8620 steel single piece 9MM bolt with a Blacknitride+(TM) finish by H&M AR15 Style Extractor 17-4 Stainless Steel Firing Pin with Spring Functions with all AR-9 style PCC magazines including: Glock, Colt Style Magazine, Endomag and MP5/MP9 Fostech Echo Binary Cut Full Auto Compatible 100% American Made About the Company: Dead Foot Arms LLC designs, develops, assembles, and markets innovative firearm parts of the highest quality for demanding applications in the commercial, law enforcement, and defense markets. Their core value is to provide innovative cutting edge products to our customers through quality processes and continuous improvement initiatives. Dead Foot Arms LLC is a Veteran owned and Operated Small Business. And their products are and always will be proudly MADE IN THE USA.