Stronghold is universally recognised as our most trusted maximum security brand. It symbolises our 240-year heritage and stands for the very best in British made locks. Tested and approved to the highest Sold Secure Diamond and Gold standards.¢Maximum security Stronghold Integrated Chain Lock¢Sold Secure Bicycle Diamond and Secured by Design¢Ultra-secure restricted key system prevents unauthorised duplication of keys¢Precision CNC machined solid steel ¢Over 500,000 key differs ¢Recommended for e-bikes and all high-end bicycles ¢Made in Britain