Prestige Smartplus Pressure Cooker Spare Gasket 57071 For Assorted Cookers Prestige smartplus pressure cooker spare gasket for assorted cookers gasket 57071 is for use with the following pressure cooker models: 6l stainless steel 57050 6l hard anodized 57051 5l aluminum 55159 6l this morning by prestige 55408 fitting instructions on reverse. Outer diameter: 25cm approx