The FrSky Normal Precision Variometer measures the rate of change of altitude by detecting the change in air pressure (static pressure) as altitude changes. Able to report altitude.When used with a FrSky transmitter like the Taranis, you can actually create mixes that use the feedback from the vario sensor. For example, you can have your motor reduce power when you reach a set altitude. An excellent feature for sites that have flight ceilings.Another nice feature of the vario is the ability to connect the FSH-01 sensor hub, thus allowing the X8R receiver's to use the existing analog sensors.Features:Capable of connecting directly to the telemetry receivers without the sensor hub.Backwardly compatible with existing sensor hub and sensors.Smart Port enabled, realizing two-way full duplex transmission.Specification:Variometer sensor-700 ~ 10000m (-2,300' - 32,800') with 1m (39") resolutionVoltage: 4 -10 Current: 30 mADimensions: 31.1mm x 18.3mm x 6mm (L x W x H)Weight: 3.1gUnits: Metric or British unitsUnits: Metric or British units