This colour changer works with both standard and bulky gauge machines. There is an adjustment given in the manual to convert it from one to the other, as the dimensions are not quite the same. It takes 4 colours. It comes with a 4 colour mast which has tighter tensions than the main mast, as you will be using thinner yarns if using it for double bed jacquard. It can also be used to knit striped ribs.