Made in the USA, our mower blade balancer is a great combination of practical, functional, and simple. It works as a typical cone balancer, but with more precision. Our balancers are made with anodized aluminum and stainless steel. They are built to last a lifetime (just like our sharpeners). The blade holder is spring loaded with a uniform cone, which allows the blade to rest perfectly centered on the balancer. It can accommodate blades with a center hole from ½" to 1 ¼" diameter. Blades with star shaped holes or other odd shapes will work, as long as the hole is symmetrical and the inside dimensions are within ½" to 1 ¼" diameter.