Drop it. Log it. View it. Share it. Know your conditions.

Know your temperature conditions anywhere with the small, rugged Kestrel DROP D1 Temperature Logger
The EASIEST way to monitor and track temperature in almost any environment – wet or dry, indoors or out
View temperature data wirelessly via Bluetooth Smart on your iOS phone or tablet with the free Kestrel LiNK app
Store thousands of data points and get months of logging on a single coin-cell battery – customize logging rate, connections and temperature alerts
See, save and share data from multiple DROP loggers with just one phone or tablet –

iOS 6 installed iPhone 4s, iPad 3rd generation, iPod Touch 5th generation and above.
Android 4.2 and higher. Works with most Android devices with Bluetooth® low energy, including Samsung Galaxy, Nexus 4, Motorola Droid, and other recent generation phones and tablets.

Kestrel DROP D1 Wireless Temperature Monitor and Data Logger Overview

Environmental Measures
	Temperature
Tips For Taking Accurate Measurements

A Kestrel DROP is the world’s easiest-to-use rugged environmental data logger. It allows you to monitor and record the conditions of any environment and easily access and chart real-time and historical data on your phone or tablet. A Kestrel DROP D1 logger can be placed wherever needed to log temperature with the data logs retrieved wirelessly and automatically to the Kestrel Connect app when within range(up to 100ft.). Kestrel DROP data loggers are designed to be used anywhere you need to track environmental conditions. DROP loggers meet military and international standards for water, dust and shock resistance (IP-67-30 minute submersion at 1m and MIL-STD-810G drop tested) and are equipped with a sturdy D-ring for hanging wherever needed.

DROP D1 Was Featured in Backpacker Magazine:

"How many times have you been out in the backcountry and wondered, 'How cold did it get last night?' or 'Exactly how hot was that scorching hike?' We wonder that all the time when we're out testing, and now with the Kestrel DROP we finally have the data we want."

Use a DROP Anywhere - Small, Accurate, Rugged and Waterproof

Hiking Drop

Kestrel DROP loggers are designed to be used anywhere you need to track environmental conditions. Each DROP measures just 1 x 1.8 x 2.4 inches (24 x 46 mm x 60 mm) and weighs just 1.2 ounces (34 grams).

The Kestrel DROP D1 employs a sealed precision thermistor mounted externally and thermally isolated for rapid response to monitor and record temperature over an operational and specification range of 14°F to 131°F (10°C to 55°C) within +/- 0.9°F (0.5°C) accuracy. Each Kestrel DROP Data Logger is powered by one easily replaceable CR2032 lithium coin cell battery that will last up to 4 months (typical conditions and logging/connection settings). The DROP D1 holds more than 13,000 temperature readings.

DROPs Are Powered by the Kestrel LiNK App

DOWNLOAD KESTREL LiNK FOR IOS

DOWNLOAD KESTREL LiNK FOR ANDROID

Kestrel LiNK is the free app that powers the DROP loggers. With Kestrel Connect, you can view real-time readings from any DROP logger within wireless range (100’ or more line of sight) via Bluetooth® low energy Each phone or tablet can connect to up to 8 DROP loggers at the same time and store data logs from many more. Min/Max/Average readings are clearly displayed and the log is viewable as a scrolling graph with detailed data for each logged point. The app also allows adjustment of the logging interval and other settings as well as real-time threshold alerts. Readings can be updated as frequently as every 2 seconds and logging time and date are automatically updated whenever connected to your smart device. Send and share real-time and logged environmental data via email, Facebook or Twitter.

Requirements:

iOS 6 installed iPhone 4s, iPad 3rd generation, iPod Touch 5th generation and above.
Android 4.2 and higher. Works with most Android devices with Bluetooth® low energy, including Samsung Galaxy, Nexus 4, Motorola Droid, and other recent generation phones and tablets.

American-Made Quality and a Five-Year Warranty

Every Kestrel environmental instrument is designed and built entirely in the USA. Kestrel’s history and focus on quality and ruggedness is reflected in the DROP’s industry-leading five-year warranty. Kestrel has been building rugged environmental instruments that help people do their jobs more safely and efficiently for more than fifteen years and has built a reputation for reliability one meter at a time.

Where Can a Kestrel DROP Be Used?

Bedroom
Basement
Attic
Kennel
Barn
Hatchery
Greenhouse
Shipping Container
Airplane
Ship
Warehouse
Factory
Humidor
Safe
Refrigerator
Field
Winery
Forest
Laboratory
Classroom
Training Center
Kitchen
Silo
Shooting range
Construction site
HVAC System

Which Kestrel DROP is right for me?

MEASUREMENTS	DROP D1	DROP D2	DROP D2HS	DROP D2AG	DROP D3	DROP D3FW
Temperature	✔	✔	✔	✔	✔	✔
Relative Humidity		✔	✔	✔	✔	✔
Dew Point Temp.		✔	✔	✔	✔	✔
Heat Stress Index		✔	✔	✔	✔	✔
Barometric Pressure					✔	✔
Density Altitude					✔
Temperature Humidity Index (THI)				✔
Wet Bulb Temperature (Psychrometric)						✔
Color Available	Red, Blue, Tan	Red, Blue, Tan	Orange	Hi-Viz Green	Red, Blue, Tan	Orange
	Buy Now	Buy Now	Buy Now	Buy Now	Buy Now	Buy Now

Features

Drop-Tested to MIL-STD-810G
Floats
LiNK Wireless Communication to Mobile Devices (Bluetooth low energy)*
Temperature Sensor (Patented External Isolated)
Waterproof to IP67 (3'/1M for 30 minutes)

Includes

Battery - 1 x CR2032
Certificate Of Conformity (Spec Sheet)
Instructions

Connectivity

Kestrel LiNK for iOS & Android

The Kestrel LiNK® App for iOS/Android allows you to Wirelessly connect with iOS and Android devices and remotely view real-time environmental data and receive alerts for changing conditions. Available for your Kestrel 5 Series Meter or DROP Logger, Kestrel LiNK also provides easy transfer of the Kestrel’s stored data log, a clear graph of all historical data. Alerts can be customized based on temperature, heat index, wind, or other measurements. LiNK enables easy firmware updates of Kestrel 5 series meters.

Data is transmitted wirelessly via Bluetooth® Low Energy within wireless range (100’ line of sight– reduced by walls and obstructions). Mobile device and Kestrel must remain within range to trigger alerts.

Learn more about what the Kestrel LiNK app can do for you.

Download from the App Store

KESTREL LiNK FOR IOS
An application that can be used to view and analyze your Kestrel data on an iOS device.

KESTREL LiNK FOR ANDROID
An application that can be used to view and analyze your Kestrel data on an Android device.

Specs

SENSORS
SENSORS	ACCURACY (+/-)	RESOLUTION	SPECIFICATION RANGE	NOTES
AmbientTemperature	0.9 °F 0.5 °C	0.1 °F 0.1 °C	14 to 131°F -10 to 55 °C	Airflow of 2.2 mph\|1 m/s or greater provides fastest response and reduction of insolation effect. For greatest accuracy, avoid direct sunlight on the temperature sensor and prolonged sunlight exposure to the unit in low airflow conditions. Calibration drift is negligible for the life of the product. For further details, see Battery Operational Temperature Limits.
Relative Humidity	2%RH	0.1 %RH	10 to 90% 25°C noncondensing	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 is typically less than ±0.25% per year.
Pressure	1.5 hPa\|mbar 0.044 inHg 0.022 PSI	0.1 hPa\|mbar 0.01 inHg 0.01 PSI	25°C/77°F 700-1100 hPa\|mbar 20.67-32.48 inHg 10.15-15.95 PSI	Monolithic silicon piezo-resistive pressure sensor with second-order temperature correction. Between 1100–1600 mbar, unit will operate with reduced accuracy. Sensor may not operate above 1600 mbar and can be damaged above 6,000 mbar or below 10 mbar. Calibration drift is negligible for the life of the product.

CALCULATED MEASUREMENTS
MEASUREMENT	ACCURACY (+/-)	RESOLUTION	SENSORS EMPLOYED
Density Altitude	226 ft 69 m	1 ft 1 m	Temperature, Relative Humidity Pressure
Dew Point	3.4 °F 1.9 °C 15- 95% RH. Refer to Range for Temperature Sensor	0.1 °F 0.1 °C	Temperature, Relative Humidity
Heat Index	7.1°F 4.0°C	0.1 °F 0.1 °C	Temperature, Relative Humidity
THI (NRC)	1.5 °F 0.8 °C	0.1 °F 0.1 °C	Temperature, Relative Humidity
THI (Yousef)	2.3 °F 1.3 °C	0.1 °F 0.1 °C	Temperature, Relative Humidity
Wet Bulb Temperature - Psychrometric	3.2 °F 1.8 °C	0.1 °F 0.1 °C	Temperature, Relative Humidity Pressure

ADDITIONAL PRODUCT INFO
Response Time & Display Update	Display updates every 1 second. After exposure to large environmental changes, all sensors require an equilibration period to reach stated accuracy. Measurements employing RH may require longer periods particularly after prolonged exposure to very high or very low humidity. WBGT requires about 8 minutes to reach 95% accuracy and about 15 minutes to reach 99% accuracy after exposure to large environmental changes.
Data Storage	Logged history stored for every measured value. Auto-store interval settable from 2 seconds to 12 hours*, overwrite on or off. D1: >13,000 data points, D2: >7,000 data points, D3: >6,000 data points.
Bluetooth® Data Connect Option	Wireless range up to 100ft\|30m. Compatible with Kestrel LiNK app for iOS (model 4s and later) and select Android products (Android 4.3 and higher) (See website for complete list of compatible 3rd party apps).
Certifications	CE certified, RoHS, FCC, IC tested and WEEE compliant. Individually tested to NIST-traceable standards.
Origin	Designed and manufactured in the USA from US and imported components. Complies with Regional Value Content and Tariff Code Transformation requirements for NAFTA Preference Criterion B.
Battery	User-replaceable CR2032 (included).
Shock Resistance	MIL-STD-810g, Transit Shock, Method 516.6 Procedure IV; unit only; impact may damage replaceable impeller.
Sealing	Waterproof (IP67 and NEMA-6)
Battery Operational Temperature Limits	0° F to 140 ° F \| -18 °C to 60°C Measurements may be taken beyond the limits of the operational temperature range of batteries by maintaining the unit within the operational range and then exposing it to the more extreme environment for the minimum time necessary to take reading.
Storage Temperature	-22.0 °F to 140.0 °F \| -30.0 °C to 60.0 °C.
Size & Weight	2.4 x 1.8 x 0.9 in \| 6 x 4.5 x 2.3 cm 1.2oz \| 34g (Lithium battery included)

DROP Data Logger Certificates of Comformity

Certificate of Conformity Kestrel DROP Wireless Data Logger (Size: 518.2 KB)

Kestrel DROP Wireless Environmental Data Logger specification chart

Downloads

DROP Data Logger Certificates of Comformity

Certificate of Conformity Kestrel DROP Wireless Data Logger (Size: 518.2 KB)

Kestrel DROP Wireless Environmental Data Logger specification chart

DROP Data Logger Instruction Manuals

Getting Started with Kestrel DROP Wirelss Environmental Data Loggers (Size: 1.2 MB)

Getting Started with Kestrel DROP Wirelss Environmental Data Loggers

Kestrel 5 Series Troubleshooting Documents

How can I submit a tax-exempt order using the website? (Size: 1.2 MB)

Here is guidance on how to submit an order through the website for Tax Exempt customers.

LiNK (Kestrel)

How to graph weather data from LiNK CSV files (Size: 667.5 KB)

This tutorial will show you how to create a graph of the data that you exported from your Kestrel 5000 series or Kestrel DROP using one of the Kestrel LiNK applications.