This is a multi-purpose plastic disc designed for the Trangia 27 cook set. It can be used as a colander, a lid for food while another pan is on the stove, a cutting board, or a base for use on snow. Please note that this disc should not be used as a lid for a pan directly on the stove. It is made of plastic and is compatible with the 27 series cookers. This product is also recommended by the Duke of Edinburgh's Award scheme.