Abus chain. The most expensive you can afford.
This one is good, but expensive:
http://www.abus.de/us/main.asp?ScreenLan...318565588m
If you can find that quality of chain (in rockwell hardness as well as thickness) 2nd hand, that would be a more reasonable price.
All you need then is a good Abus lock - which is also expensive.
Alarms and disc locks are for false sense of security.
As well as cheap fat strong looking chains-locks.
This one is good, but expensive:
http://www.abus.de/us/main.asp?ScreenLan...318565588m
If you can find that quality of chain (in rockwell hardness as well as thickness) 2nd hand, that would be a more reasonable price.
All you need then is a good Abus lock - which is also expensive.
Alarms and disc locks are for false sense of security.
As well as cheap fat strong looking chains-locks.
Most things done in a hurry need to be done again - patiently.