Marks USA Survivor series cylindrical lever locksets is offered in four lever styles: conventional cylinder, or IC core for "Best" size cores, Schlage as well as others. The locksets feature a lifetime mechanical warranty and are UL-Listed for 3-hour fire rating. The supplier's HI-SECURITY Cylinders feature a locking principle that includes the combination of standard pin tumbler cylinder with a sidebar locking mechanism which corresponds to a "security wave" designated by unique shaped side pins which correspond to a factory milled groove on the key. The Cylinders are bump-, pick- and drill-resistant and can be supplied UL437 or Non-UL Optional.
