BRACKET-SPORTS / Bracket Sports Attachment for mounting a dynamo and light, compatible with thick front forks For cross bikes, ATBs, MTBs, small-wheeled bikes, etc. Compatible with front fork diameters of approximately Φ21mm to 32mm Product Specifications: Size: Front fork mounting diameter: Approximately φ21-32mm. Weight: 96g (actual measurement). Product Details: An attachment to be added to front forks without a dynamo mounting base. Ideal for the front forks of sports bikes such as cross bikes, MTBs, ATBs, and small-wheeled bikes. Supports forks up to 32mm in thickness. Please refrain from price negotiations.