They work as long as three fletch is all you want. Be sure to get the right one because there are several different ones, depending on whether you're using carbon or aluminum/wood shafts, left, right or straight fletching, and feathers or vanes (the arms for vanes are, sometimes, a pain to use with feathers and vice versa). They do sell extra arms, so you can save a little over getting two fletchers. It also fits, easily, in your bow case or tackle box if you travel to hunt.