The Double Pin scope adopts the BulletProof pin technology found in our multi-pin sights and incorporates it into a single vertical pin with dual fiber optic aiming points. The Double Pin is lens and light ready without any additional adapters. It also comes with the option of either a single alignment ring or a triple alignment ring for those archers looking for better accuracy in varying lighting situations. Mounted on a 1/4-28 threaded rod, it will fit all of the Hogg Mobb series adjustable sights.