Sontara: popular DuPont product that has a soft cloth like feel. It is fluid repellent, but fluids will strike through with extended exposure. Autoclavable. Sontara is available coated with a clear poly film which makes it impervious. However, the impervious material cannot be autoclaved and is provided sterile.
Plain Sontara, folded to open to long dimension first
55″ x 77″ sterile, tyvek pouch