Our chain lock is made of stainless steel, and it is safe and non-toxic. It is strong and durable for long use. The chain lock can be installed on either wood or metal door, convenient to use. Features: High quality stainless steel material, safe and non-toxic, hard and sturdy. Security guard-- easy to install and operate; can not be unlocked from the outside, unlocks easily from the inside. The door chain is strong and durable for long use, not easy to deform. The door chain is thickened, abrasion-proof, and convenient to use. Flexible installation: can be installed on either wood or metal door. Specifications: Condition: 100% Brand New Material: Stainless Steel 1#: Black, 201 Stainless Steel 2#: Silver, 201 Stainless Steel 3#: Silver, 304 Stainless Steel Chain Length: approx. 196mm/ 7.71in Lock Length: approx. 123mm/ 4.84in, 63mm/ 2.48in Thickness: approx. 2.86mm/ 0.11in Weight: approx. 113~118g/ 3.98~4.16oz Package List: 1* Chain Lock 1 Bag of Screws Note: 1. Please allow 0-2cm error due to the manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. 3. Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering. .