ND Series locks have been the most popular Schlage product ever since Walter Schlage invented the cylindrical lock in 1920. The ND Series is ANSI/BHMA Grade 1 certified and performs beyond the Grade 1 standards. The lock withstands 3,100 in-lb. of abusive lever torque, as well as 1,600 lbs. of offset lever pull for protection against pry bar attacks. The lock is not only strong from attacks, but it also shows nearly zero droop or wobble after 16 million cycles.
All ND Series locks come in 10 finishes, nine lever designs and use an ANSI 161 door preparation, commonly used with cylindrical locks. They are ideal for all new construction and retrofit applications.
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