Cube ACID Chain Extension for ACID Frame Locks Add an extra layer of security to your bike with the Cube ACID Chain Extension. Designed for use with compatible ACID frame locks, this plug-in chain allows you to secure your bike to a fixed object while using the same key as your frame lock. Featuring 8 mm hardened steel chain links, the chain is highly durable, wear-resistant, and corrosion-protected for reliable everyday use. A protective plastic sleeve helps prevent scratches to your bike's frame, while the low-noise design minimizes rattling. This chain extension is a perfect match for the frame lock found on the Cube Supreme Hybrid Deluxe One 600, providing a simple and convenient way to increase your bike's security. Features Compatible with ACID frame locks 8 mm hardened steel chain links Corrosion-resistant and wear-resistant construction Low-noise design Protective sleeve prevents frame scratches Convenient one-key operation Secure your bike to racks, posts, and other fixed objects with the durable and easy-to-use Cube ACID Chain Extension.