American Fan Co. centrifugal fan. Model BI-245. Blower has up to a 5500 cfm @ 2.8" static pressure and a high temperature rating of 650° F. Blower has a 24" diameter inlet and a 19" x 25" outlet. The blower fan blade is 24.5" diameter x 8" wide. Has a 15 hp 1760 rpm motor. Requires 575 vac 3 phase electrical supply.