The Kainpo Dog Drive Adapter Ultra Swing is an adapter model that can be installed on the fork tube instead of the bike frame. Aid for safe pulling hobby with 1-2 dogs. The adapter quickly lifts the loose cord away from the tire. Thanks to its flexibility and mobility, it is gentle on cables and brake hoses. Can be installed in the frame or fork tube. Suitable for bicycles and scooters. A sure choice for a racing enthusiast! Specifications: The spring can be removed with a 4mm hex key. The spring has a strength of 4 mm. Contains two mounting straps 54mm and 38mm so that the adapter can be installed on most frames. Weight: 509g NOTE! When attaching to the fork tube, you also need a Nylon sleeve .