YSHIELD® GK5 | Primer ConcentrateYShield Primer Concentrate GK5 is particularly useful for priming old painted surfaces, brittle surfaces and absorbent substrates. A high quality primer concentrate, it boosts adhesion, penetration and absorbency. Primer should be applied as the undercoat to Yshield Paint. YShield EMF Shielding Paint Primer use Mix the concentrate 1 part to 4 parts of water Use a paint roller to apply the primer Typical coverage is 37. 5m2 l of concentrate, depending