The On Guard Mastiff Chain Lock is made of 10mm ultra-hardened, titanium-reinforced steel links with a 13mm padlock.Includes 5 laser-cut keys, 1 lighted key; features non-slip chain cover and ultra-hardened, titanium-reinforced steel links10mm links with 13mm padlock and includes $3,001 anti-theft protectionItem SpecificationsLock Size3.7" x 10mmBracket IncudednoLock StyleKeyed