 It is designated as the M110A1 and uses an aluminum upper receiver instead of steel to meet weight requirements, weighing unloaded and reaching some loaded and with accessories; the M110A1 features a Geissele M-LOK rail handguard, Schmidt & Bender 3–20×50 PM II Ultra Short telescopic sight, Geissele optic mount, OSS SRM6 suppressor, 6-9 Harris bipod and mount, and a collapsible stock with adjustable comb.In May 2018, the U.S. Marine Corps will begin receiving the CSASS, also to replace the M110.In March 2018, the Army announced that a version of the G28/M110A1 would be issued to infantry squads as the service's standard Squad Designated Marksman Rifle (SDMR).