Thistle Bonding Coat is a versatile, gypsum undercoat plaster suitable for use on a wide range of backgrounds. It is an ideal base coat for smooth or low to medium suction backgrounds, such as plasterboard, medium density blockwork, engineering bricks and surfaces treated with Thistle Bond-it. It provides an ideal basecoat, preparing walls for skim finishing. This pre-mixed gypsum undercoat plaster is easy to spread, easier to rule and darby. Complies with EN 13279-1, type B4/20/2 & C3/20.