UV vellum: a transparent wood pulp paper product with a specific weight and grain. UV Vellum is used to print black and white vector artwork for the exposing process of creating a photomask. UV Vellum works best with a monochrome laser printer. This product can be used with Rayzist Magic Dark Toner Repair Kit. UV Vellum is a less expensive alternative to the Laser Film product. 8.5"x14" Legal size, 500 sheets per ream.