This is a Leapers, Inc. - UTG Rail, model MTU004SS.
Leapers 9" UTG rail system for AR rifles is a mid length" super slim free float handguard with proprietary attachment design in an extremely compact profile. It is super lightweight with a rail at the 12 o'clock position and forms a continuous picatinny top section. It includes three user detachable 2-slot rail sections for the 3" 6" and 9 o'clock positions. It has an internal anti-rotation tab for rock solid locking and an ergonomic slim tubular profile for most positive handling.
Features:
Black finish
Accommodates low-profile gas block
Works with standard AR15 upper receivers