This is a very rare removable carry handle rear sight for older Knight’s Armament Company (KAC) SR-25 rifles with a cutout for their removable shell deflector. This will work with any AR10 or SR25 style .308/7.62x51 rifle, and has an A2 style aperture with windage knob. These are very hard to come by these days.
I’m looking to get $120 or best offer, and trades are welcome.
Note: also posted on GunBroker
Thanks for looking!