Dow 1200 OS Primer is used to improve adhesion and accelerate adhesion build-up of silicone sealants to a variety of substrates. Dow 1200 OS is a moisture curing primer that is supplied as a dilute solution of reactive materials in low viscosity siloxane. Dow 1200 OS Primer is classified as low-solids adhesive primer according to the following regulations: Rule 1168 for Adhesives and Sealant Applications published on the South Coast Air Quality Management District and Rule 8-51 for Organic Compounds, Adhesive and Sealant Products published by the Bay Area Air Quality Management District. The VOC Inclusive value reported on the product label follows the definitions on these regulations. The VOC Exclusive value on the product label does not apply. DOWSIL 1200 OS 4099614 Primer improves adhesion of silicone sealants to many substrates, provides more uniform and stronger bonds, conforms to South Coast and Bay Air Quality Management District Regulations for Architectural Sealant Primers, has a low VOC at 76 g/l and is formulated for low toxicity. Dow 1200 OS 4099614 solvent used does not deplete the ozone layer and is considered Ozone Safe (OS) and, as a primer, it is suitable for weathersealing and structural glazing applications.