Bike USA Stabilizer Wheel Kit Adult Training Wheels, Heavy duty steel bicycle wheels and hubs. Perfect Training wheels for a Mountain Bike. Steel Construction with Plastic coated u-bolts which protect the bicycle frame from damage during install and removal. These training wheels come with 16" inflatable tires and tubes , Recommended for Adults or Children who are physically impaired 0r mentally handicapped. This adult trainer kit will mounts to most 24" - 27" bicycles. Great for people with fear of falling or balance issues. Not recommended for Electric, folding, or recumbent bicycles. Great Replacement to purchasing an adult trike. Ideal for a standard frame bicycle with a 26 inch tire