The casters themselves are good, if overpriced. The hardward that comes with the casteres was too large for my JoBox Piano box. They call the 5/16" bolts self threading, but the holes in the jobox feet are 1/4" and pretty thick steel. So that's only self threading if your piano box is upside down so you can lean on an impact wrench. The "2nd" set of hardware they send is 3/8 so that's right out. In reality, be prepared for a trip to the hardware store.
