The shoemaker's wheel pricker (approx. 20 cm long) has a metal wheel (approx. 2 cm in diameter) with sharp pointed teeth, which is attached in a U-shaped bracket to the end of a metal shaft; the shaft is attached to a wooden handle with a tang. It is used to mark the holes on the leather where the awl will go through later. The distance between the teeth varies according to the desired distance between the stitches.
See also the saddler's wheel pricker and wheel pricker for stenciles. [MOT]