The winbag is made from a fibre reinforced material making it very tough and durable. It is 2mm thick when deflated meaning it can be pushed into the smallest of gaps. Once inserted it can be inflated up to 50mm (two inches). Deflating the win bag is simple and can be done at the press of a button. This inflatable shim, or inflatable wedge is very useful for window fitters, kitchen installers and a whole host of other jobs.