Ideal for K-12 schools and universities with high-traffic areas, the 11 Line Grade 1 cylindrical lock from Sargent features true interlocking between the lock body and latch for a high level of strength. A rugged design features interlocking construction between the cast/machined stainless steel lock body and the latch, exceeding ANSI/BHMA A156.2 Series 4000 Grade 1 cycle test standards by a factor of 10. The lock withstands 3-1/2 times ANSI/BMHA torque force – more than 3,000 in/lbs – on a locked lever.