Low-Profile Stainless Steel Power Vented (PTP/BTP) The ideal solution for heating a commercial workspace like a warehouse or workshop or studios. The horizontal power vented PTP unit heater line delivers 80% thermal efficiency in a small business-friendly package. The blower model BTP allows customers to add ductwork onto the unit to distribute heat and air better. This unit is an excellent fit for greenhouse applications and other situations that need better and more flexible air movement. Also, it offers up to 82% thermal efficiency. https://www.modinehvac.com/products/unit-heaters/commercial-gas-fired-heaters/low-profile-stainless-steel-power-vented-ptp-btp/