Crude C4 is a fraction obtained from the refining of crude oil or natural gas that comprises various hydrocarbons with four carbon atoms. This fraction includes butanes, butylenes, and other higher hydrocarbons. Crude C4 undergoes further processing to separate and purify its components, which are then utilized in different industries. Butanes serve as fuel gases and feedstocks for gasoline blending and petrochemical production, while butylenes are used in the manufacturing of plastics, synthetic rubber, and other chemical products. The specific composition and applications of crude C4 vary depending on refining techniques and market demands for specific hydrocarbon products.