Experimental pure component vapor pressure data for hexafluoropropylene (R1216) and hexafluoropropylene oxide (HFPO) are presented. Experimental vapor-liquid equilibrium (VLE) data are presented at two temperatures, (273 and 3 13) K, for four binary systems: R1216 + toluene, HFPO + toluene, hexafloroethane (RI 16) + R1216, and RI 16 + HFPO. The measurements were undertaken using both a "static-analytic" apparatus fitted with a pneumatic rapid online sampler injector (ROLSI) and a "static-synthetic" PVT apparatus. The experimental vapor pressure data were regressed to obtain correlated parameters for the Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) equations of state with the Mathias-Copeman alpha function. The binary VLE data were regressed to obtain correlated parameters for three different model combinations: the PR equation of state with the Wong-Sandler (WS) mixing rules, the PR equation of state with the modified Huron-Vidal first-order (MHV1) mixing rules, and the SRK equation of state with the WS mixing rules. The Mathias-Copeman alpha function and the nortrandom two-liquid (NRTL) excess Gibbs energy model were used in Conjunction with the equations of state and mixing rules. In general, the PR equation of state with the WS mixing rules provided the best correlation for the experimental data. The critical lines for the supercritical systems R116 + R1216 and R116 + HFPO, calculated with the PR equation of state with the WS mixing rules, are also presented.