One Horse LLC 5.56 NATO 30+1 16" Black Threaded Barrel, Black Receiver w/Picatinny Rail, M-LOK Handguard, One Horse M4 6 Position Black Polymer Stock, Black A2 Grip The OH-15 16 5.56/.223 mid-length delivers dependable performance, smooth cycling and solid accuracy. Its the go-to workhorse for the range, home defense, training and everyday tactical use and made in the USA. Featuring a threaded, SOCOM barrel, mid-length gas system; A2 grip; Mil-Spec buffer tube and a One Horse M4 6 position stock. Includes a 30rd Magpul magazine.