1. Made from die-cast SUS-304 stainless steel; with excellent brushed nickel finish---aesthetic look which is unique to SUS-304#SS 2 door chain lock. Extra thick: 1.85mm (with the same thickness as a coin), heavy duty chain latch for interior door, 100% durable. 3. Lock length=13cm (phone length about 5inch), width=3.5mm; Chain length=20cm 4. Safety Guard - Easy to install and use; easily unlocked from the inside > 5. Mounting hardware included: 1 door chain lock with mounting screws.