This is a Bushnell Boresighter, model 740001C.
Bushnell Magnetic Boresight Riflescope Accessory 74-0001C - Works on all calibers and firearms. Revolutionary design eliminates the need for arbors. Magnetically attaches to the muzzle to facilitate a quick sighting in. Etched glass reticle.
Features:
For use on all calibers and firearms
Easy sight in
Etched glass reticle
