HB Body 534 High Build 2K Grey Primer 5 Litre Kit Compliant 4L & 1L HardenerHB Body 534 2k primer is a high quality 4:1 high solids primer whitch is fast drying with excellent adhesion to all metals and plastic bumpers.You can apply direct to unsanded OEM panel by adding 50% thinner. It also has superb filling properties leaving a smooth easy sand surface.