The lock has a built in security system that activates the alarm if anyone tries to put something foreign into the lock for example - a wrong key. Corrosion resistant. Provides perfect security for your property. This high security design is rainproof, rust proof & weatherproof. It is ideal for garden sheds and houses, garages, caravans, bicycles, gates etc. The alarm resets automatically. Corrosion Resistant with hardened Zinc Alloy Body. Suitable for all weather conditions Simple to operate and easy to install. Heavy-duty, waterproof and very good quality. Read Less