We recommend this tough-as-nails U-lock if you really want to send a message to a would-be thief to mess with someone else's bike. This is the u-lock to choose if you lock up your bike in high theft areas, or for an expensive electric bike.
The New York has been called the daddy of tough u-locks because the dual bolt central locking mechanism is armored with two steel sleeves, which makes it extremely resilient to both hammer blows and other striking attacks. The center keyway helps defend from leverage attacks to the u-lock too.
While there is no 100% theft proof lock, you'll feel more secure using this 16mm hardened MAX-Performance steel shackle U-lock to resist bolt cutters and leverage attacks.
If you really want to deter theft of your prized bike, we recommend you get this U-lock, plus the heavy-duty Evolution Series 4 Integrated Chain. This combination of both U-lock and chain will significantly reduce theft risk.