* 5/16" Wide Copper foil tape has an acrylic adhesive backing designed to withstand the heat of soldering.  The copper foil tape is used as the base for your soldering.  The 5/16" width is perfect for wrapping 2 pieces of 1mm thick glass with art sandwiched between, with room to trim any un-even edges. Also great for thicker glass. 15 feet will go a long way for small projects!