Our custom PVC labels are usually sewn(*) to products. But not every soft PVC label can be sewn, it has to have either one or both of the following specs.: 1.The thickness of the base of the label should preferably be less than 1mm. If the base label is thicker than 1mm (usually 1.5mm or more), it should include a sewing channel, which is nothing but a thinner rim around the label, about 1mm in width and usually of less than 1mm in thickness.