Metal Shell: The shell of the stretchy cord is made of strong and durable zinc alloy, not easy to deform, and resists corrosion in daily life. The thick steel wire is not easy to break and has undergone tens of thousands of tensile tests. 【Latest Improvements】Compared with the old one, the stretchy keychain on the back has an additional round buckle. Attach back clips or circular buckles to belt loops, bags, lanyards, and backpacks without the attached objects falling off easily. Bold Steel Wire: The key lanyard is made of thick steel wire, which is not easy to break. The steel wire is about 70cm long, can be retracted automatically, which is very convenient. 【More convenient】The retractable cord can be used for ID card, ID cards and keys, etc. You can pass your work permit without taking it out. You can also open the door without taking out the key from the belt. This will make your life more convenient. Note: The data are all measured manually, please allow 1-3cm error due to