The practical bias tape formers from Prym enable bias tapes of any length to be perfectly formed to border any fabric edges or patchwork blankets. By cutting the strips of fabric at an angle of 45 degrees to the grain of the fabric, the bias tape becomes elastic and can also be used perfectly in curves. After the strips of fabric have been cut to size and connected to one another, the fabric is inserted into the wide opening of the bias tape former and pulled through. On the flat side of the useful helper, the perfectly folded diagonal strip can be pulled out and smoothed directly with the iron. The bias binding is quick and reliable and can simply be rolled up for further use.