This is a ProMag Rail Covers, model PM015A.
PM015A The polymer panel covers 1913 Picatinny rails" protecting the rail when not in use. The panel cover provides a secure and comfortable gripping surface. The panel is constructed of a proprietary glass-filled" Zytel-based" black polymer. The panel may be custom fit by shortening to cover specific lengths of exposed rails. Package includes four (4) rail panel covers.
Features:
1913 Picatinny Rail
11 Rib cover panel
Four pack
