Each Lower Receiver features the custom model designation (DTOM15) and a custom serial number range (SNK-XXXXX). Gen 2 Improvements Upper Tension Screw – Allows users to fine tune the fit of the upper and lower receiver through the use of a nylon tipped tensioning set screw inserted in the grip tang of the lower receiver. Features specific to the Brownells M16A1 Upper Receiver are the original A1 profile, with no shell deflector, A1 rear sight housing and proper carry handle contours. The upper starts off as a 7075 T6 aluminum forging, then is machined to mil-spec dimensions. Once machined, the upper is finished with a matte black hard anodized finish.
Ga subshell from which electron removed to form 1 cation