Product code: K4500HORUS - 0845H£0.00 inc. VAT
The Kestrel 4500NV Pocket Weather Tracker with integrated HORUS® Atrag™ ballistics software calculates precise aiming solutions based on real-time atmospheric conditions, user specific ballistics and multiple target data.
When shooting long range, even the lightest of breezes will affect the bullet, no matter what speed or ballistic coefficient it has. Also, any change in geographical location (determining coriolis and spin drift) or altitude, atmospheric pressure, temperature and humidity will impact the firing solution required to hit the target. In a robust, pocket sized instrument the Kestrel provides instant and accurate measurement of wind speed and direction with all other critical environmental parameters that affect a bullet's trajectory. The integrated HORUS software automatically updates the firing solution based on this real-time weather data. Each user inputs their own ammunition's ballistic variables and velocity along with the rifle's data (bore-sightline height, twist rate and direction along with zero range etc.) into the Kestrel 4500NV HORUS. These gun and bullet settings may be saved to a library for future quick reference.
24 HOUR SHIPPINGProcessing Mon-Fri
on all in-stock models
FREE UK DELIVERYFree standard delivery
Next day delivery available
RETURN POLICYNot 100% satisfied?
Return within 21 days
Corrections for• Elevation
For those with after dark requirements, the Kestrel 4500NV Horus comes with a low intensity red back-light to preserve night vision.
To enable in depth analysis of data at a later time, the Kestrel with Horus ATrag ballistics can be set up to log data automatically or manually. The stored data can also be uploaded to a PC via an additional Kestrel PC interface. With the Bluetooth model, data may be streamed live via Bluetooth wireless technology.
The Kestrel with Horus ATrag ballistics is compact and weighs only 112g. It is IP67 waterproof and MIL-STD-810F rugged. The Kestrel's robust design has survived years of use by the military world-wide; their quality is backed up by a 5 year warranty.
The Kestrel with Horus ATrag ballistics is powered by two easily replaceable, AAA batteries and has two power saving modes to prolong battery life.
|Target||Active Targets||-||A through E||1||5|
|Wind Speeds 1 and 2 (for bracketing)||WS1 or WS2||mph||0||50|
|Direction of Fire||DoF||o'clock||1||12|
|Target Direction of Movement||TD||Left to Right OR Right to Left|
|Gun||Name Characters||-||0 through 9; A-Z; a-z; -+/.:&* and space|
|Twist Direction||RTd||Left OR Right|
|Density Altitude (computed)||Dalt||ft||-10732||32767|
|Coriolis||Coriol||Yes OR No|
or Air Velocity
|m/s||0.1||Larger of 3% of reading, least significant digit or 20 ft/min||0.6 to 60.0 m/s
0.6 to 40.0 m/s
|1 inch diameter
impeller with precision axle and
low-friction Zytel® bearings.
Start-up speed stated as lower limit, readings may be taken down to 0.4 m/s | 79 ft/min | 1.5 km/h | .9 mph | .8 kt after impeller start-up.
Off-axis accuracy -1% @ 5° off-axis; -2% @ 10°; -3% @ 15°.
Calibration drift < 1% after 100 hours use at 16 MPH | 7 m/s.
Replacement impeller (NK PN-0801) field installs without tools (US Patent 5,783,753).
|ft/min||1||18 to 11,811 ft/min
118 to 7,874 ft/min
|km/h||0.1||2.2 to 216.0 km/h
2.2 to 144.0 km/h
|mph||0.1||1.3 to 134.2 mph|
1.3 to 89.5 mph
|knots||0.1||1.2 to 116.6 knots
1.2 to 77.8 knots
|Beaufort||1||0 to 12 B|
|Temperature||°F||0.1||1.8 °F||-49.0 to 257.0
-20.0 to 158.0
|Air, water or snow temperature. Hermetically-sealed, precision thermistor mounted externally and thermally isolated (US Patent 5,939,645) for rapid response. Airflow of 2.2 mph | 1 m/s or greater provides fastest response and reduction of insulation effect. Calibration drift negligible.|
|°C||0.1||1.0 °C||-45.0 to 125.0
-29.0 to 70.0
|Relative Humidity||%RH||0.1||3.0 %RH||0.0 to 100.0%
5.0 to 95.0% non-condensing
|Polymer capacitive humidity sensor mounted in thin-walled chamber external to case for rapid, accurate response (US Patent 6,257,074). To achieve stated accuracy, unit must be permitted to equilibrate to external temperature when exposed to large, rapid temperature changes and be kept out of direct sunlight. Calibration drift +/- 2% over 24 months. RH may be recalibrated at factory or in field using Kestrel Humidity Calibration Kit (NK PN-0802).|
|Pressure||inHg||0.01||typical 0.04 inHg
max 0.07 inHg
|0.30 to 32.48 inHg||Air pressure at the location. Adjustable reference altitude allows display of station pressure or barometric pressure corrected to MSL. Monolithic silicon piezoresistive pressure sensor with second-order temperature correction. Pressure sensor may be recalibrated at factory or in field. Kestrel 2500 and 3500 display continuously updating three-hour barometric pressure trend indicator: rising rapidly, rising, steady, falling, falling rapidly. Kestrel 4000 series displays pressure trend through graphing function.|
|hPa (mb)||0.1||typical 1.5 hPa
max 2.5 hPa
|300.0 to 1100.0 hPa 10.0 to 1100.0 hPa|
|PSI||0.01||typical 0.02 PSI
max 0.04 PSI
|0.14 to 15.95 PSI|
|°||1||5°||0 to 360°||2-axis solid-state magnetoresistive sensor mounted perpendicular to unit plane to permit operation while measuring wind speed. Declination/variation adjustable for True North readout. Accuracy of measurements dependent upon unit's vertical position. Self-calibration routine eliminates magnetic error from batteries or unit and must be run after every full power-down (battery removal or change).|
|Cardinal||16 Points||5°||0 to 360°|
|mph||1||10%||Refer to stated ranges for wind speed.||Effective wind relative to a target or travel direction. Calculated from wind speed, wind direction and target heading. Auto-switching headwind/tailwind indication.|
|Wind Chill||°F||0.1||1.8 °F||Refer to stated ranges for wind speed and temp.||Perceived temperature resulting from combined effect of wind speed and temperature. Calculated based on the NWS Wind Chill Temperature (WCT) Index, revised 2001, with wind speed adjusted by a factor of 1.5 to yield equivalent results to wind speed measured at 10 m above ground. Specification temperature limits established by WCT Tables.|
|Heat Index||°F||0.1||3.6 °F||Refer to stated ranges for temp. and relative humidity.||Perceived temperature resulting from the combined effect of temperature and relative humidity. Calculated based on NWS Heat Index (HI) tables. (Specification temperature limits established by HI tables.)|
|Wet Bulb Temperature (Psychrometric)||°F||0.1||3.6 °F||Refer to stated ranges for temp., relative humidity and pressure.||Temperature indicated by a wet bulb psychrometer under forced aspiration. Calculated from temperature, relative humidity and pressure.|
|Dewpoint||°F||0.1||3.6 °F||Refer to stated ranges for temp. and relative humidity.||Temperature to which the air must be cooled at a constant pressure for water vapour to condense into water. Calculated from temperature and relative humidity.|
|Altitude||ft||1||typical 50 ft
max 98 ft
|-2,300 to 85,000 ft||Height above Mean Sea Level ("MSL"). Temperature compensated pressure (barometric) altimeter requires accurate reference barometric pressure to produce maximum absolute accuracy.|
|m||1||typical 15 m
max 30 m
|-700 to 25,900 m|
|Density Altitude||ft||1||246||Refer to stated ranges for temp., relative humidity and pressure.||Air density converted to equivalent sea level elevation at the International Standard Atmosphere. Calculated from temperature, pressure and relative humidity.|
|Max/Avg Wind||Max and average wind calculation may be started and stopped independently of data logging of other values, along with all other wind-related functions: air velocity, crosswind, headwind/tailwind, wind chill, WBGT, TWL, evaporation rate.|
|Data Storage & Graphical Display, Min/Max/Avg History||Minimum, maximum, average and logged history stored and displayed for every measured value. Large capacity data logger with graphical display. Manual and auto data storage. Min/Max/Avg history may be reset independently. Auto-store interval settable from 2 seconds to 12 hours, overwrite on or off. Logs even when display off except for 2 and 5 second intervals (code version 4.18 and later). Data set capacity by model shown.|
|Data Upload||Requires optional PC interface (USB or RS-232) or Bluetooth enabled model and provided software.|
|Adjustable power consumption and radio range from up to 30 ft | 9 meters. Individual unit ID and 4-digit PIN code pre-programmed for easy identification and data security when pairing and transmitting. Employs Bluetooth Serial Port Protocol for data transmission.|
|Display & Backlight||Multifunction, multi-digit monochrome dot-matrix display. Choice of aviation green or visible red (NV models only) electroluminescent backlight. Automatic or manual activation.|
|Response Time & Display Update||All measurements except those based on relative humidity respond accurately within 1 second. Relative humidity and all measurements which include RH in their calculation may require as long as 1 minute to fully equilibrate to a large change in the measurement environment. Display updates every 1 second.|
|Clock / Calendar||Real-time hours:minutes:seconds clock, calendar, automatic leap-year adjustment.|
|Operational & Storage Temperature Range||The operational temperature range of the liquid crystal display and batteries is 14° F to 131° F / -10 °C to 55 °C. Measurements beyond the operational range can be taken by briefly exposing unit to extreme conditions such that the display and batteries remain within the operational range. Storage range -22 °F to 140 °F / -30 °C to 60 °C.|
|Auto Shutdown||User-selectable -- 15 or 60 minutes with no key presses or disabled.|
|Languages||English, French, German, Italian, Spanish.|
|Certifications||CE certified, RoHS and WEEE compliant. Individually tested to NIST-traceable standards (written certificate of tests available at additional charge).|
|Battery||AAA Alkaline, two, included. Average life, 400 hours of use, reduced by backlight or Bluetooth radio transmission use.|
|Environmental||Waterproof (IP67 and NEMA-6). MIL-STD-810F, Transit Shock, Method 516.5 Procedure IV; unit only; impact may damage replaceable impeller.|
|Size & Weight||5.0 x 1.8 x 1.1 in / 12.7 x 4.5 x 2.8 cm, 3.6 oz / 102 g.|
|Colour Options||Olive Drab | Desert Tan|
|The manufacturer reserves the right to amend the specification and therefore the information in this document may be subject to change|
|Kestrel 4500NV with HORUS ATrag Ballistics Data Sheet|
|User Instruction Manual|
|Kestrel 4500NV with HORUS ATrag Ballistics Instructions|
|Horus Ballistics Downloads|
|Horus Gunloader Software (ZIP file)
(currently not compatible with software version 4.76)
|Horus Help files (ZIP file)|
|Certificates of Conformity|
|Sample Certificate of Conformity|
|Kestrel Product Catalogue|
|Kestrel Pocket Weather Meters Product Catalogue 2012|