Spartan Precision Equipment Heavy Duty Optics Adapter Black. It is compatible with both MagnaSwitch and Disc-Lok fittings. Specifications for Spartan Precision Equipment Heavy Duty Optics Adapter: Manufacturer: Spartan Precision Equipment Color: Black Weight: 2.4 oz Features of Spartan Precision Equipment Heavy Duty Optics Adapter CNC machined from 7075-T7351 aluminium billet with a hard-anodised black finish Designed to attach to cameras and other optics with standard 3/8"-16 or 1/4"-20 threaded female mounting points Includes a carbon control arm for fine control Package Contents: Spartan Precision Equipment Heavy Duty Optics Adapter Spartan Precision Equipment SP06-018-R: Heavy Duty Optics Adapter Black