Ignition Battery: 4.8-8.4 NiCd or NiMH, 6.6V LiFe or 2S LiPo pack Gasoline/Oil Mix: 30:1 Replacement Spark Plug: 1/4-32 SIZE or equivalent dle Speed: 1500 rpm/min Static Thrust: 17.2 lb (7.8 kg) @ 328 ft (100 m) altitude 15.9 lb (7.2kg) @ 5,900 ft (1800 m) altitude