Silicone (VMQ, vinyl-methyl-silicone) rubber is a synthetic elastomer with a backbone of alternating silicon and oxygen atoms, featuring pendant organic groups (methyl, vinyl, phenyl) attached to silicon for tailored properties. Standard silicone O-ring compounds are typically peroxide-cured, while platinum-cured variants offer superior purity for medical/FDA applications. Silicone O-rings excel in extreme temperatures (-60°C to +200°C or higher), with outstanding resistance to ozone, UV, weathering, corona, and many oils/chemicals/solvents, plus excellent dielectric properties and FDA compliance for food/pharma use. They retain superior flexibility at low temperatures but exhibit low tensile strength, poor tear/abrasion resistance, and are best suited for static sealing.