Hexaethylcyclotrisiloxane, also known as D3, is an organosilicon compound with the chemical formula (C2H5)6Si3O3. It is a clear, colorless liquid with a mild odor. One of its key properties is its low viscosity, making it easily customizable for a wide range of applications. Additionally, this silicone precursor is highly stable and resistant to extreme temperatures, moisture, and chemicals, which contributes to its long shelf life and durability.