BCM® Rail Mounted Folding Battle Sight – A4 Front (manufactured by Troy Industries for Bravo Company MFG, Inc)
Use with all M4, M16A4, SR25 and AR10 Flat Top configured weapons.
FBSA4F Front Picatinny rail mounted folding sight for M4/M16A4/SR25/AR10
This is the new model with the M4 Style Housing and Square Post. If you have a lot of training and trigger time on the M16 and M4 iron sights, this configuration front sight is generally faster to use.