The little trailer I used at Batsto Sunday worked perfectly. When I got home I unloaded the trailer and drove out back with it to pick up a little sand. When I got into the yard the right tire was flat. Awww crud! Pulled off the wheel and with a small flat bar I pulled the tire off the rim. Found a tiny pin hole in the tube fron a welding spatter bead. Monday at the tire place they stuck on a little tire patch and she is back together. LAST night the LEFT tire is now flat. This time there is a cut on the valve stem. Lucky I had a brandnew 400x 8 tube and stuck it together. The oringinal tubes are really thin like the ones you use for Radial tires. Yes they are from china. Get aload of the extra rubber from the mold. Guess you could glue it on for extra tred wear. Picture of weld job.