This is a Magpul Industries Handguard known as the MOE SL, model MAG1048-BLK.
The Magpul SL Hand Guard for the SP89/MP5K is a high-strength" injection-molded polymer handguard solution that provides the user with improved ergonomics" anti-slip texturing" and M-LOK compatible slots allow mounting of modern accessories. It's an injection-molded handguard solution for SP89/MP5K and clones that provides increased utility and enhanced control of the firearm. The SL Hand Guard offers M-LOK compatible slots at the 3" 6" and 9 o'clock positions" and features a large muzzle-end hand stop" similar to the HK "K" style handguard.
Features:
M-LOK compatible slots at 3, 6, and 9 o'clock positions
Increased firearm utility and control
High-strength polymer construction and threaded fastener provides rigidity and stability without the need for a user-adjusted tensioning mechanism
Large muzzle-end hand stop similar to K style handguards
Aesthetics reminiscent of legacy MP5 furniture lines as reimagined by Magpul
Serves as 922(R)-compliant component for imported SP89/MP5K clones
Compatible with SP89 / MP5K and clones with 5 barrel