This is a 120mm (4.7″) wide by 22M long roll of Kapton tape (Polyimide). Enough to cover about 50 8×8″ glass sheets. We prefer this size since it’s easier to apply than full width sheets. Printing over heated Kapton taped glass allows for excellent adhesion of melted plastic and gives the bottom of your print a nice smooth finish. After many hours of printing, refresh your printing surface with this stuff. This tape can handle temperatures of up to about 280C. We’ve tested tape from several different manufacturers and chose the best. *** APPLICATION TIP: To minimize the seam from laying to sides down, just spray some lightly soaped water onto the glass and tape. Lay the first side down, slide to position, then squeegee the water out.