ATG tape is widely used by professional framers throughout the world. This acid free double-stick tape is used to stick double or triple mats together, and attach mats to the mounting board or foam core. This tape is great for many other uses as well - mounting photographs, graphic arts, layout work, drafting, etc. This product is similar to 3M #924 tape. Each roll is 1/2 inch wide (1.27 cm) by 36 yards long (32.9 M.) Packed in a case of 12 rolls. Made in USA.