Titanker Bike Chain Lock, Security Anti-Theft Chain Bike, 10Mm Thick Chain). Secure Portable: The key can only be pulled out when locked, which prevents the key from being lost. Titanker bike lock comes with 2 keys. You can take one of the keys to use in daily life, and you can leave another key at home in case you accidentally lose one Heavy Duty High Quality: With 8mm thicker security heavy-duty chain links, our bike lock is made of heavy-duty steel known for its cut-resistance. Lubricate the bike chain lock hole and keyhole regularly, this will prolong the lock's service time Protective Cloth Sleeve Dust Cover: Chain is enclosed in protective cloth sleeve, which effectively protects the bike lock chain from rusting and scratching Safety Tips: Never leave your bike locked outside for long periods of time. Especially in high crime areas. No bicycle lock is 100% secure Portable Safe Size: The overall length of the bicycle chain lock is about 3.3 feet. The links are about 1.97 inches long and about 0.32 inches inch thick. Lock Weight: 2.5 pounds