This is iron-on stretch-stop tape. This is the straight type. The straight type is for shoulders, pocket openings, armholes, zipper areas, etc. The half type is for necklines, armholes, etc., and other small items. Please use according to the material. White is 1.2cm wide and 50m long, Black is 1.0cm wide and 50m long. This is a set of white and black. Occasionally, the bulk may appear different due to the winding of the core or the adhesion of the glue. This is an error in the manufacturing process, so please be understanding. We also have the half type available, so please take a look.