Silicone sealants are important materials for professionals and craftsmen in the building industry. There is hardly a joint or crevice that is not filled with silicone sealant. The typical quality features are high - tear-resistant, water-repellency and colour-fast. An important contribution to this is made by the low-viscosity base oils used for this purpose, more precisely the Pilot® extender oils from Haltermann Carless. We spoke with Jan Boerrigter, Commercial Manager for Middle Distillates, and asked him how Haltermann Carless provides technical advice to manufacturers of silicone seals in the development of formulations, the new hydrogenation plant and individual supply chain concepts.