I forgot to say that how it is stored also matters as does where you live! ALL fusibles like moisture! If your room is dry or over heated, it will ruin your fusibles so fast it will hurt! If heat/dryness is the issue then store your fusibles in a sealed tupperware or ziploc container/bag! The less hot dry air it gets the better! Same if you have TOO much moisture...it can make it separate from the paper!