Counterfeited Leupold Mark 4® riflescopes and more recently, counterfeited Leupold Prismatic riflescopes have begun to arrive with increasing regularity at the firm’s Beaverton, Oregon, headquarters for service. These products are not manufactured by Leupold and are not covered by the Leupold Full Lifetime Guarantee.
In general, most of the scopes appear to originate from Hong Kong (People’s Republic of China), and have “Leupold Mark 4” laser engraved on the bottom of the turret in a silver etch, while the black ring on the objective is etched in white and does not include the name “Leupold”. The scopes also do not bear the Leupold medallion, a mark all Leupold scopes will always possess. An authentic Mark 4 riflescope will always be engraved black on black and have the name “Leupold” engraved on the black ring.
Identifying Marks:
Counterfeited Leupold Prismatic riflescopes:
The absence of a serial number and barcode on the bottom of the scope is the easiest way to identify these counterfeits. A brass ring may be visible when looking into the objective and screws can be seen on the top of the finger click adjustments under the caps. The product name is not engraved on the black ring.
Identifying Marks:
FOG HORN 
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