Specification: Features: Suitable for children's trailers and most bicycles. Usable as a convenient and safe hitch for bicycle trailers to be attached to bike's rear axle. Made of durable material,sturdy and wear resistant. Easy to assemble and storage. Decrease time needed to switch your trailer onto a new bicycle easily.Just connect with trailer towbar,then you can switch it quickly. Notice: We don't promise this hitch works with all trailers and bikes. Please refer to your trailer's model and attaching hole size before placing order. Thank you Actual color may be slightly different from the image due to different monitor and light effect Please allow 1-3cm deviation due to manual measurement Specifications: Material:Steel Hole diameter for the bike bolt: 11mm Hole diameter for the trailer's handle bar: 7mm Recessed area diameter where axle nut screws onto: 21mm Base plate length: 55mm Package List: 1x Trailer Hitch Mount 1x Buckle