The chain attachment system is a small U-shaped lock with Zefals Z safe technology, guaranteeing resistance to shocks and torsion. It is supplied with 2 keys.Key Features:Z Safe: - Powerful double locking system. High resistance against impacts and twists.Transport:Wraps easily around most bike framesProtective Coating: The chain is encased in fabric to protect the bike's paintwork.2 Keys included: In case of lossSpecifications:Level Of Security: 8 - For areas with a very low risk of threatMaterial: SteelMounting: Wraps easily around the frameKeys: 2 includedDimensions: 90 cmDiameter 6 mmWeight: 700g