The Triplett HS10 Heat Stress WBGT (Wet Bulb Globe Temperature) Meter monitors indoor/outdoor heat index to help limit the danger of heat-related injury. It simultaneously displays Air Temperature, Humidity and Wet Bulb Globe Temperature (WBGT) or Heat Index and updates every 20 seconds. Features programmable audible and visual WBGT and Heat Index alarms with an adjustable audible alarm volume (75dB/60dB/mute)and 4 indicators that display heat stress alert level (Caution, Extreme Caution, Danger, Extreme Danger). An In/Out function switch measures WBGT with or without the effects of direct sunlight. °F/°C switchable. Wall mount for placing meter in a permanent position and tripod mount can be used to free-up your hands when taking measurements over an extended amount of time. Includes (2) AAA batteries and armstrap. 1-year warranty. For outdoor athletic training and events, construction, iron and steel foundries, brick firing plants, glass facilities, boiler rooms, mining sites and other areas where heat index levels should be monitored.