Practical function: bike hitch linker is a professional bicycle trailer hook, which is very useful. Rugged material: The cycling trailer coupler clutch is made of Metal, which is durable and has a long service life. Easy to install: Bicycle trailer clutch has a complete hook arm and hook connector, which can be easily installed without other tools. Good compatibility: The hook adapter can be compatible with general- bicycles and electric bicycles. Use place: Bicycle trainer clutch operates on quick release or flat axle wheels and is not suitable for disc brakes. Colour:silver Material:Metal Package Contents: 1 x Bike Trailer Hitch Coupler Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.