F Luth-AR A1 Delta Ring/Slip Ring, Black, 223 Caliber, BL-09A $12.19 BL09A show more like this Dvor F A1 Delta Ring $14.99 BL-09A show more like this $8.99 Flat Rate Dirty Bird Industries F Luth-Ar Ar-15 A1 Delta/Slip Ring - Ar-15 Delta/Slip Ring Black $15.99 BL-09A show more like this $12.50 Brownells