You are bidding on an A4 size piece of ceramic gasket paper  for Temps up to  1100 deg c.  Used for flue pipe door hatch or brush hole gaskets as well as stove door glass gasket. It is 3mm thick. We can supply any size up to 600mm wide x 15m long if needed. The gasket in the picture we have cut as an example. It is very easy to cut with a pair of scissors.