Features:Product Type:Trailer HitchSize:The diameter of the bicycle rear axle mounting hole: 11mmdiameter of the mounting hole of the link trailer: 7mmThe diameter of the recessed portion where the shaft nut is screwed: 21mmBase plate length: 55mmWeight: 158g Material: stainless steelType: Child TrailerModel: see pictureColour: blackScope of delivery:1x bicycle trailer hitch with safety pin Coupling Steel Coupling AdapterSafe and reliable: Compared to conventional bicycle trailer hitches, these ensure a better and more secure hold on the quick releaseExtra robustness and Flexibility: Thanks to the high maneuverability of the trailer, you can also drive the system on winding roads without any problems. This allows you to react in good time to sudden dangersSafety: Due to the low center of gravity, the trailer is less prone to rolling away and tipping over. Even if your bike falls over, the bike trailer stays upright. The coupling thus offers maximum safety for your loved ones