This is a Samson Manufacturing Corp. Sight, model QF-FFS-FRS.
Samson Manufacturing Corp. Sight Picatinny Black Package Includes Samson FFS HK Front Sight and Samson FRS A2 Rear Sight 6061 Aluminum" Mil-Spec Hardcoat Anodized for Durability
Features:
Flip up sight set
FFS HK front sight and FRS A2 rear sight
Fits picatinny