If you already have enough keys in your life, the RockyMounts Shackleton U-lock is the ticket. You can program in your own four digit code.
The Shackleton boasts a hardened steel shackle and a double deadbolt lock mechanism that resists drilling, picking, bumping, pulling and prying.
Silicone cover over the steel U will protect your bike frame.
Includes a frame mounting bracket and includes free installation onto your bike when purchased in-store.
We think this is the least expensive bike lock you should buy.
If your bike has quick release wheels, consider a double ended cable for even greater security.