Place your bike in solitary with the Blackburn San Quentin Bike U-Lock. The 18mm cut-resistant alloy steel shackle with anti-scratch liner will spoil any theft-attempt without scratching up your beautiful ride. The bump-proof, pick-proof dual-bolt locking mechanism will stand up to Hollywood's most clever jewel thief, and the $4,000 theft replacement guarantee has you covered in the event of the unthinkable.