The 4″ has a 1/2″ center hole, the 6″ has a 5/8″ hole with removable reducer to 1/2″, and both are rated up to 4,500 rpm. The 4″ wheel has a bristle width of about 1/4″ and the 6″ wheel’s width is about 3/8″.
The 4″ has a 1/2″ center hole, the 6″ has a 5/8″ hole with removable reducer to 1/2″, and both are rated up to 4,500 rpm. The 4″ wheel has a bristle width of about 1/4″ and the 6″ wheel’s width is about 3/8″.