My buddy almost had his bike stolen. It's this chain from harbor freight, I think 10mm links, although the lock was replaced with a circular disc type Heavy Duty Padlock ChainHe's lucky he's weird and was sleeping on his couch instead of in bed or he never would have heard the noise of the chain rustling outside. The dude was using 36" bolt cutters and a beach towel to hold the chain still. Strangest part is the thief walked past at least 10 bikes locked up with cables, onto the second story balcony to try cutting this pretty heavy duty chain that was protecting a $200 amazon fixie.