Venture is the best foil we have found on the market. It sticks well and is cut very uniform. Choose the size foil by the thickness of glass and the width of the lead line you want showing. Standard foil is copper on both sides. The black and silver backed foils are copper on the outside and silver or black on the adhesive side. Use the color backed foils when you have transparent glass where you can see the inside of the foil. Choose the color backing that will match the final color of your solder (Copper patina, black patina, or natural silver) and you'll have a much neater job.
