Small 14g tub of Black Swan plumbers silicone grease.
Black Swan silicone grease is a 90% pure silicone grease-like product. Composed of inert amorphous silica fillers and selected silicone fluids. Contains no petroleum additives. Formulated for many plumbing applications including making hard turning taps (faucets) work smoothly, and lubricating stems of taps, valves, ballcocks, etc.
Silicone grease works at high temperatures (up to 230°C), can be used on rubber or synthetic O-rings and is resistant to a wide range of chemicals.