Naphtha (petroleum), C4-12, butane-alkylate, isooctane-rich; Low boiling point modified naphtha; [A complex combination of hydrocarbons obtained by alkylation of butanes. It consists predominantly of hydrocarbons having carbon numbers predominantly in the range of C4 through C12, rich in isooctane, and boiling in the range of approximately 35 °C to 210 °C (95 °F to 410 °F).]