Ram Board's Seam tape is 3" width to give more allowance to cover Ram Board seams. The kraft backing makes it easy to tear off and install as well as makes it recyclable. Because of its contractor grade adhesive, it should not be taped directly to finished floors and surfaces. Like most tape it is not vapor permeable and should be avoided in areas where curing floors need to breathe. If you need a breatheable tape, use Ram Boards Vapor Cure tape.