Dog Bike Trailer, Durable Frame, Easy to Connect and Disconnect to Bicycles, Safety Tether, Collapsible to Store, Suitable for Medium Sized Dogs

It is very easy to assemble and is well built. You really just need to pop the wheels and the handle on and you are good to go. The materials look like they are good quality and there is even a clear plastic flap (and a separate mesh flap) to keep rain off my dog when but still let them see in the front.