This item is almost unusable. I bought this to adapt a Yasorn drill chuck to an angle grinder which it is often paired with as it is often purchased together. However, the problem here is that almost all angle grinders are 8 1/2" with a 5/8" shank. Inch (male). The internal (female) thread of this product is M10 and the external (male) thread is 5/8". , so they reversed it and misdescribed it, so if like me you buy it with the intention of attaching a chuck to the grinder, it just won't work because it won't fit.