I bought this product for balancing metal boat props for use on a gas racing boat. For me this product is simplicity at its best and functionally brilliant. It gives me confidence to know that my props can be balanced as close to perfection as is possible. That is thanks to the strong magnets suspending the balancing spindle giving extreme sensitivity with minimal rotational friction. If you buy this product I strongly recommend taking a little time to properly finish & polish the surface of the magnets and read the instructions carefully. I spent about an hour setting the product up as recommended for maximum precision. It is a one off job to do that and very easy; time expended that I consider will pay me back big time in getting the most out of this balancer. Finally 10 out of 10 goes to Leeds Model Shop for their informative and excellent way that they promptly processed my internet order.