Sold Secure Gold Rated  The Kryptonite Evolution Series 4 1016 chain lock is very powerful for its size. You can use this chain lock in moderate to high crime areas - even better when used in addition to a D-lock or heavy duty cable lock. Kryptonites Evolution is so secure it is rated Sold Secure Goldthe highest accolade a bike lock can receive and very insurer friendly. The chain itself is made from hardened triple heat-treated steel chain with 10mm links. It will resist strong attacks. The Evolution Series 4 1016 comes with 3 keys - so multiple spares - including an LED key so you can see what you're doing in the dark. Key Features Sold Secure Gold ratedThe hardened triple heat-treated boron manganese steel chains include 10mm six-sided linksThe integrated chains secure with a new patent-pending integrated Evolution series 4 lock headThis innovative series of chains also feature a patent-pending pin-less design which secures the chain to a hardened deadbolt and allows for n