Review on Onguard X4 Shackle Disc Lock - Ultimate Boxer Edition by Justin Vasquez

I have purchased several of these locks and they are among the most secure locks. Thick, 4 pins on the shackle, 5 keys and so far very reliable. I have many OnGuard locks and chains - the customer service has been great. It's compact but will fit most lock cables and large chains (10mm and up - just check the dimensions). If you are locking a scooter or motorbike I highly recommend a combination lock and chain - Onguard 8017LPT - for my scooter the lock is perfect - the chain goes heavy through the tire rim and offers the plus 'O' medallion pin. "The ring at the end of the chain lengthens the chain (although sometimes I wish it was 1ft longer) – just check the bike to make sure the lock head doesn't fit through the spoke holes.