007-10 and 007-20 (10% and 20% phenyl substitution, respectively) are the Quadrex designations of phenyldimethylpolysiloxane phases. The phenyl substitutions contribute to the "induced dipole" selectivity of these phases. A column coated with either phase displays excellent efficiency and thermal stability. These phases provide an excellent alternative for drug and environmental pollutant analyses where greater retention of aromatic compounds is necessary.