Calibers: 5.56 NATO/223; 7.62 NATO/308 Win., 6.5 Creedmoor. Modular Ambidextrous Rifle System (MARS) features an ambi' safety selector, mag-release button, bolt release, and bolt catch. Monolithic Rail Platform upper receiver, ambidextrous charging handle. S-A bolt carrier group. The MARS-L has a 16" 5.56×45 (.223) chrome-lined 1:7" RH twist barrel. Other models include MRP, Quad, Piston, and PDW (10.5" barrel). MARS-H has 16" 7.62 NATO chrome-lined 1:10" RH twist barrel. Other models include Battle Rifle (13.5" lightweight barrel w/pinned LMT 3-prong flash hider), DMR (with 20" 1:11.25" RH twist 5R cut barrel), and 6.5 DMR (20" 6.5 Creedmoor stainless-steel 1:8" RH twist barrel). Add 25% for the MARS-H 7.62 and 33% for the MARS-H 6.5 DMR.