The Master Lock No. 8195 Heavy Duty U-Lock features a 6in (15cm) wide hardened steel body for maximum strength and reliability. The 1/2in (13mm) diameter double locking shackle is 8-1/4in (21cm) long and made of hardened steel, offering extra resistance to prying, cutting, and sawing. The disc key cylinder prevents picking attacks. The Limited Lifetime Warranty provides peace of mind from a brand you can trust.