Spencer offers an indirect fired GSE heater, the "NANOOK." Designed to heat 737s down to regional and corporate jets, the NANOOK'S "instant heat" will deliver hot air at 170 F above ambient in subzero climates. This quiet, low maintenance heater with a small footprint will amaze you with its 500,000 Btu per hour output. For more information visit www.spencer-manufacturing.com.