High quality: Our bicycle trailer coupler is made of iron with black enamel coating, which is sturdy and firm, not easy to deform or twist, corrosion resistant, not easy to damage. With fine texture, can withstand heavy loads. Safety design: The bicycle trailer coupler bracket is equipped with a connecting pin, the pins can hardly be opened, even after you install them, they will not fall off easily, and the trailer is less likely to swing and tilt. Package: The package includes 1 set of bicycle trailer coupler, the size of the diameter of the hole to which the axle is attached: 1.09 cm. Diameter of the hole in the coupler to which the trailer is attached: 0.7 cm. Length of the base plate: 5.5 cm. Easy to use: The bicycle replacement coupler is easy to install without any other tools. First attach the towbar to your bike, then use the connecting pin to fix the trailer bracket, and the trailer is connected successfully. Wide application: With our bicycle rear rack axle adapter, you can pick up your son or daughter as well as your pets by bike and enjoy this quick interaction and have a nice time cycling together. Suitable for allround bicycles