I didn't purchase this on the amazon website, but through a local pet suppy store. I was so excited until I actually tried to put this on my bike. To sum it up the metal parts were VERY, VERY poorly tooled. At first I thought I might have bought a defective item, so I took it back to the store. When I opened the second one I was shocked to see the same problem. The nuts were all scratched up and would barely fit over the bolts. The large nut only fit after about half a can of wd40 and A LOT of elbow grease from my boyfriend (LAME! because I am strong and shouldn't have to ask somebody to do it for me). I finally had it all attached and took my dog for a ride around the neighborhood. That part was okay. When I came home I tried to remove the pin, so I could ride my bike without the attachment. The pin would not come out! I had to take my bike apart to take this stupid thing off. Then I had to pound the pin with a mallot to remove it.Really really lame...