I put them 3 inches off the ground so the 5 year old could ride the bike and one of the wheels came off the 2nd day. I would say about 2 hours of riding time tops. Plus, make sure you pick your color. I saw pink and thought it was pink. My fault.Works as described. My problem is getting the boy to now ride the bike (he's still addicted to Minecraft)We got 20" bicycles for our very tall girls and these training wheels happened to fit correctly on the particular bicycles. They are okay but I would not recommend them for anyone over 45 pounds - they will probably bend and break.Training wheels what more can i sayThis product is a pice of crap i m sorry to said that, when i got delivery i opened my boy and the bag has a hole in the button and i mever could found my hard wear i couldn even use,, and is not a contact number were i can ask my money back is a waist dont buy itHorrible instructions, bad design and would never buy again. I would have returned it if I didn't try to make it work and heavily modify it so it will fit and allow the tire to touch the ground. Bad design.When I received this merchandise, it never work the wheel kept coming off. Now the child does not have training wheels to learn how to ride her bike. We had a horrible Xmasmy daughter can ride her barbie bike now and she is sooo happy they match great with her pink barbie bike