Front Door Security Chain

This is a mortise lock that has an this is a mortise lock that has an adjustable spring loaded hook latch projection for surface mounted sliding patio doors constructed of wood aluminum and vinyl with handle sets with vertical keyway position when in the locked position. It also fits doors using w f manufactured handles. A fairly recent entry into the market of door chains is one that activates a screeching alarm if the thief attempts to force the door while opened on the chain and at the same time it sprays the intruder with a liquid containing a dna trace chemical that is unique to your house.