The Flame Tech HD-1-2 is a Size 2 heating head designed for natural gas or propane, with fuel consumption of 100-150 SCFH. It operates at 10-15 PSIG fuel pressure and 50-70 PSIG oxygen pressure, with listed heat output ranges of 100,000-150,000 BTU/h for natural gas and 237,100-355,650 BTU/h for propylene.