Inevitably someone will fill one of my vac coin mechs with nickels and pennies then punch it when it gets stopped up. Seems they always punch the timer area and I've had vacs with brand new decals get a hole right in the clear window for the timer. I have been just putting clear packing tape over the window, but before long I have to replace it and it looks bad under it. Anyone try anything else that would work better and last longer?