Patent Pending. Finally a true “drop-in” PU Picatinny scope mount for Mosin-Nagant rifles with high wall receivers. Simply remove your existing PU scope and use this mount to use your modern scopes. It works on most aftermarket and reproduction PU scope mount bases also. No modification required. Guaranteed to hold zero, while shooter still retains the ability to use the iron sights up to 500 yards! This scope mount is made of 7075-T6 aircraft-grade aluminum, weighing only 5.25 ounces.