Our bench spotting scope stand employs two large clamping plates to lock the stand securely to the bench. A bench thickness of one fourth inch to 12 inches is easily accommodated. The scope mounting head moves smoothly up and down on the 18 inch stainless steel shaft for proper scope height adjustment. The head locks in place with a comfortable knob and contoured locking piece. The scope mounting head incorporates a double spring loaded adjusting mechanism which permits easy target acquisition. The scope mounting surface is designed to mount one fourth to 20 threaded scopes with a mating surface of 1 to three fourths by 2 to one fourth inch or less (almost all field and spotting scopes with threaded mounts). We usually mount the scope to the left side of the bench so all we have to do is move our head off the riflescope to view the results of our shooting. If you shoot off the bench using open sights or lower powered scopes, this is a piece of equipment that puts your spotting scope to great use.