Range:O2: 0 to 21%, CO: 0 to 2000 PPM (4000 PPM Max for 15 minutes), CO2: 0 to 30%, Temp. (Flue and net): 32 to 1112°F (0 to 600°C), Efficiency: 0 to 99.9%, Excess Air: 0 to 250%.Accuracy:O2: ±0.2%, CO: ±10 PPM < 100 PPM else ±5% of reading, CO2: ±0.3% reading, Temp. (Flue and net): ±2°C ±0.3% reading, Efficiency: ±1% reading, Excess Air: ±0.2%.Resolution:O2: 0.1%, CO: 1 PPM, CO2: 0.1%, Temp. (Flue and net): 0.1°F/C, Efficiency: 0.1%, Excess Air: 0.1%.Ambient Operating Temperature:32 to 104°F (0 to 40°C).Power Requirements:(8) AA alkaline batteries, installed functional, user replaceable, (4) AA NiMH batteries, included, user replaceable (charger included) or optional power adapter.Pre-Programmed Fuels:Natural Gas, Light Oil, Propane, Butane, LPG, and Wood Pellets.Probe:11.8″ (300 mm) length x 0.25″ (6 mm) diameter with 7.8″ (200 mm) stainless steel shaft.Hose:10 ft (3 m).Weight:1.7 lb (0.77 kg).Agency Approvals:CE.