Booyah Medium Dog Stroller & Pet Bike Trailer and with Suspension - Florescent Green Bike trailer kit INCLUDED. No need to purchase trailer kit separately. OURS PULLS DIRECTLY CENTER BEHIND THE BIKE. Makes it difficult to pull on sidewalks when not directly center behind bike. Suspension and 12 inch front air filled swivel wheel. Pneumatic wheels. Not plastic. Bike hitch method and NOT clamp method which can bend frame and wear bike paint Size: Medium up to 60 lbs tow capacity but please see that your can fit within the interior dimensions. 40lbs dog seem to be the max size to fit. Instructions appear to be missing. Please look for instructions under the cushion. Rear wheels and handlebar are quick release. Adjustable handlebar. Organizer sold separately. For post purchase support contact the seller. Do not contact Amazon.