C.R. LAURENCE S1L2100 CRL General Purpose Silicone Primer. CRL S1L2100 Primer promotes adhesion of certain one-part CRL Silicone Sealants to a variety of construction materials such as coated glass, metal, stone, masonry, and plastics. A coverage rate of about 25 square feet (2.3 m2) per container is recommended on rough or porous substrates. On smooth metal surfaces a coverage rate of 50 square feet (4.6 m2) per container is possible. Allow the primer to dry for 15 to 60 minutes depending on substrate and weather conditions, and apply the silicone sealant within 8 hours. Check Spec Data for complete application instructions.. Part Numbers Variations: S1L2100