Stained glass copper tape (copper tape), the standard Edco. I've used various kinds, but it's still number 1 in ease of use. Even when darkening solder, the copper tape with a copper-colored back (regular) does not detract from the beauty of the glass, so this color is recommended for anything other than clear transparent glass. We recommend using the copper-colored back (copper color) because it does not bleed black from the edges and does not lose its sparkle, whether it's transparent colored glass or opaque glass. The width is 5.6mm, which is ideal for glass from 2mm to 4mm, and it's a very easy-to-use regular type. I bought extra when purchasing for my own creations. ● This is the latest arrival, not something that has been stored for a long time and has lost its stickiness. *No discounts are available except for bulk purchases.