The Magpul ACSL Adaptable Carbine Stock Light is a dropin replacement buttstock for AR15M16 carbines using milspec sized receiver extension tubes, A streamlined version of the ACS, the ACSL utilizes the same center storage compartment and cheek weld but removes the battery tubes for a slimmer, lighter weight package, Note: There are two basic sizes of M4 Carbine receiver extensions buffer tubes: milspec and commercialspec, If you have a commercialspec extension on your rifle, make sure to order the CommercialSpec ACSL, Please see the Related Info section above to determine which tube you have, Color: Black, Made in USA, Mounts on milspec sized carbine receiver extension tube not included from manufacturers such as Colt, Armalite, S and W, LMT, and others please see the note below, Sloping cheek weld provides a wide contact surface for user comfort, Storage compartment in tail of stock with positive latching access door on right hand side, Supplemental friction lock minimizes accuracy robbing wobble, Shielded release latch prevents snagging and accidental operation, Premium chromesilicon lock spring provides positive locking and long service life, Replaceable 0, 30 Rubber ButtPad offers an antislip surface and increases impact protection, Compatible with Magpul ASAP and other receivermount sling attachments, Sling Mounts, Mid Included reversible QD Swivel Sling Mount fits up to 1, 5 pushbutton swivels swivel not included, RearBottom 1, 00 sling loop, Optional Accessories:, Extended Rubber ButtPad, 0, 55, Enhanced Rubber ButtPad, 0, 70, Specifications:, ACSL, MilSpec stock configuration, Length, Maximum: 7, 95, Width, Maximum: 2, 17, LOP Adjustment Range: 3, 25, LOP, M4 Collapsed: 11, 75, LOP, M4 Extended: 15, 00, SKU: TCLGR1560