My name is Jim and I have a business called Nicola Construction Co.in the Detroit area. I have worked in construction for 35 years. I build additions, create kitchens baths and additions. One day my arms both developed tennis elbow after lifting heavy loads of drywall and plywood. I noticed it was the sheets that were ruining my arms. 15 years ago I made a cart. It worked ok but had many problems. I decided to follow my call in developing this tool about 5 years ago. I have tried every tire, I have tried to carry anything I could on this. When there was a problem I remade my prototype. 4 prototypes and 20 wheels later as well as a specially added rubberized anti slip strip, and here it is. I have selfishly used it for about 15 years now and I cant tell you what a big difference it has made. I wish I had it when I started! Being 50 and starting at 15 years old I can tell you it wold have increased profits, kept my whole body more preserved. Recently I had it engineered and made it out of the most durable polypropylene I could find. That way it does not scratch our customers houses and gives it a handle in design to carry it with and made it stronger and softer at the same time. I use it on lawns, dirt roads, terrible conditions really. Thanks for reading and share this along. it cost a boatload literally to make this but that is how much it has helped me.