If you need serious protection, but want a lock that is compact, the Bordo Big 6000 folding lock is exactly what you're looking for!
The Bordo Granit features 5.5mm steel bars with an extra soft coating to prevent damage to your bike's paint. The lock body is color matched and features the same silicone cover for that soft touch feel. The linked construction allows the Bordo Big 6000 to fold into a compact unit for easy storage. The bars, links and case, as well as the supporting elements of the locking system are made of special hardened steel.
Two keys are supplied with the lock.