Lets Go Pet Walker, Bicycle Dog Leash for Small / Medium Dog.4 colors, Gold, Purple, Blue, Red. Color may vary. Easy install and quick release, no tool needed Safety- single spring provide elasticity and avoid an unexpected pulling force while your dog meets your neighbors cat. A biker will not be controlled by the dog. And Unhindered  Will not interrupt a bikers thigh Fit for Small / Medium size dog Fit all kind of bike  Fit all size seat post 25.4-31.8mm Light weight  Only 350g*. All aluminum made. Aluminum 6061, various color: Blue and Red