Rustins quick dry primer and undercoat greywhite rustins gypu1000 this 1l tin of primer and undercoat from rustins is suitable as a primer on new and bare wood mdf plaster brickwork or cement used as an undercoat on primed or painted surfaces and may be overcoated with water or solvent based finishing paints rustins gypu1000 quick dry primer amp undercoat grey 1 litre