The double cylinder design requires a key to operate from both the inside and outside, adding an extra layer of security, particularly for doors with glass panels. The adjustable latch of the door deadbolt lock fits doors with thicknesses ranging from 1-3/8" to 1-3/4", and accommodates backsets of both 2-3/8" and 2-3/4", making it versatile and suitable for a variety of door types.
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