Insul-Lock HR Universal Primer is a water-based primer designed for use with Insul-Lock HR over mineral surfaced, gravel surfaces and highly oxidized smooth built-up roofs. Insul-Lock HR Universal Primer penetrates weathered surfaces to ensure maximum adhesion between existing surfaces and the new Garland roof system. This VOC-compliant primer is easy to apply and does not require mixing. A red tint makes application easy, as applicators can easily see where it has already been applied.