Review on PetSafe Happy Ride Steel Dog Bike Trailer: Secure, Convenient and Spacious - Ideal for Medium and Large Sized Pets by Chris Huff

Really good quality for the price. I put something harder on the bottom, under the liner that came with the kit, for more stability. I just assembled it for a 65lb English bulldog and assembly was very easy. A medium is recommended for his weight but he is a large dog in width only short legs so I took a large and he was the right size. For my large and long German shepherd I need an XLarge. I would recommend one size larger than recommended. Easy access for dogs through the rear window, this is the only way for the dog to get inside. Three pockets outside (nice) and 2 metal halter/collar loops inside. The top, front and back all zip up nicely, while the clear rain cover rolls up nicely on the front and attaches with an elastic loop to a long wand-like button.