TOPCOAT TPO Red Primer is slightly tinted to distinguish primed areas on bright white TPO membranes. The surface of the treated area must be clean of all dirt, dust, and debris and be completely free of moisture prior to application of the primer. This Red Primer is a VOC-compliant, solvent-based thermoplastic liquid to be applied to new or aged EverGuard TPO membranes where adhesion of TOPCOAT water-based coatings or MajorSeal Liquid Flashing is desired.