The sales hype for the silicon molding materials, to justify there higher price, says "You can make the mold once and use if hundreds of times! The first customer pays for the mold (you keep it) and all the rest is pure profit!" Well it is a permanent mold and can be used for many, many years. However, in the last 30 or so years that I have made molds, I have not even once, used a mold more than once except on the same project. The stuff is expensive, but also very convenient and faster to use in certain applications.