Onlyfire LP Air Mixture Valve for Liquid Propane Fire Pits, 100% Soild Brass Mixes air with your incoming LP gas 150,000 BTU Valve 1/2" female or male (with included adapter) NPT on burner side and 1/2" male NPT on incoming side See our entire line of burners and fire glass crystals For propane (LP) only, improves propane burn effectively. Results in higher quality flame appearance and reduces sooty normally associated with propane