These pieces enable you to connect your eBike to the Folding Deer Trailer, Folding Cargo Trailer, or the Little Cub Hauler. While our trailers are capable of working with many other eBike brands, some models may require an axle replacement for proper connection. For compatibility information specific to your non-Bakcou eBike, we recommend visiting Robert Axle Project - the industry leader in axle compatibility solutions. Hitch Compatibility Guide: Mule and Storm (not Jager) 3/8-10mm Hitch Note: All new trailer orders include this standard hitch, but you can order this if you need a replacement or additional hitch. Flatlander, Kodiak, Grizzly, and Timberwolf 12mm Hitch Note: This hitch looks similar to the 3/8-10mm but has a wider opening for larger axle sizes. If you own one of these models and are ordering a trailer, you must also order this hitch separately. Mule Jager and Storm Jager Jager Hitch Adapter Note: This adapter threads onto your axle, allowing you to attach the standard 3/8-10mm hitch that comes with the trailer. Scout Jager and Mav3 10mm x 6mm Adapter Note: This adapter replaces your axle nut, enabling you to attach the standard 3/8-10mm hitch that comes with the trailer. Scout 229mm x 1.5TPI SDWT Axle Note: This is a complete axle replacement for your bike. After installation, the standard 3/8-10mm hitch that comes included with the trailer can be attached.