Segal Dropbolt (Double sided with key cylinders on both sides)>

"The original SEGAL lock was developed in 1912 by Samuel Segal, a New York police officer, who saw the need to protect residents from thieves “jimmying” or spreading the door frame to gain entry. Improvements over the years have changed the original design and made the Segal Vertical Deadbolt one of the strongest locking devices available through the retail channels. !"

Features & Benefits:
Hand assembled in the United States using only the finest solid cast-bronze and brass. Suitable for residential or commercial applications. Cast bronze case, bolt and strike with a 5-pin cylinder provides maximum strength for total protection from both sides. Inside and outside cylinders are keye4d the same. Jimmyproof design and exclusive shutter guard prevents the lock from being opened if the cylinder is wrenched out. Maximum holding power in any installation.