System Specifications


Sensor glucose assay method
Amperometric electrochemical sensor
Sensor glucose reading range
40 to 400 mg/dL
Sensor size
2.9 mm height and 21 mm diameter
Sensor weight
1 gram
Sensor power source
One silver oxide battery
Sensor data
Up to 14 days
Sensor memory
Up to 14 days (glucose readings stored every 5 minutes)
Sensor transmission range
33 ft (10 meters) unobstructed
Operating temperature
50 °F to 113 °F
Sensor Applicator and Sensor Pack storage temperature
36 °F to 82 °F
Operating and storage relative humidity
10-90%, non-condensing
Sensor water resistance and ingress protection
IP27: Can withstand immersion into 3 ft (one meter) of water for up to 30 minutes. Protected against insertion of objects > 12 mm diameter
Operating and storage altitude
-1,250 ft (-381 meters) to 10,000 ft (3,048 meters)
Radio Frequency
2.402-2.480 GHz BLE; GFSK; 4.6 dBm EIRP
Please refer to the User's Manual for updates to the information.

Blood glucose assay range
20 to 500 mg/dL
Reader size
95 mm x 60 mm x 16 mm
Reader weight
65 grams
Reader power source
One lithium-ion rechargeable battery
Reader battery life
4 days of typical use
Reader memory
90 days of typical use
Reader operating temperature
50 °F to 113 °F
Reader storage temperature
-4 °F to 140 °F
Operating and storage relative humidity
10-90%, non-condensing
Reader moisture protection
Keep dry
Operating and storage altitude
-1,250 ft (-381 meters) to 10,000 ft (3,048 meters)
Reader display timeout
60 seconds (120 seconds when test strip is inserted)
Radio Frequency
Near Field Communication (13.56 MHz RFID); ASK Modulation; 124 dBuV/m; 1.5 inch communication range; 2.402-2.480 GHz BLE; GFSK; 2dBm EIRP*
Data port
Micro USB
Minimum Computer Requirements
System must only be used with EN60950-1 rated computers
Mean service life
3 years of typical use
Reader cleaning and disinfection
The Reader has a mean use life of 3 years, which is 156 cleaning and disinfection cycles (1 cycle per week for 3 years).
Power Adapter
Abbott Diabetes Care PRT31887 Output: 5V, 550mA or 0.55A Operating temperature: 50 °F to 104 °F
USB Cable
Abbott Diabetes Care PRT21373 Length: 37 inches (94 cm) Color: Yellow

Please refer to the User's Manual for updates to the information.

Electromagnetic Compatibility (EMC)
FreeStyle Libre 3 Reader - FCC ID: QXS-LIB02
FreeStyle Libre 3 Sensor - FCC ID: QXS-LIB03S

  • The System needs special precautions regarding EMC and needs to be installed and put into service according to the EMC information provided in this manual.
  • Portable and mobile RF communications equipment can affect the System.
  • Use of accessories, transducers, and cables other than those specified or provided by Abbott Diabetes Care could result in increased electromagnetic emissions or decreased electromagnetic immunity of the System and result in improper operation.
  • The System should not be used adjacent to or stacked with other equipment and that if adjacent or stacked use is necessary, the System should be observed to verify normal operation in the configuration in which it will be used.
  • The device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) The device may not cause harmful interference, and (2) the device must accept any interference received, including interference that may cause undesired operation.
  • Changes or modifications not approved by Abbott could void the user’s authority to operate the equipment.

Security Measures and Quality of Service:

Security Measures:

The communication between the Receiver (App or Reader) and Sensor during an activation scan is a short range Near Field Communication (NFC) method which makes it difficult to interfere with or intercept during transmission. The communication between the Receiver and Sensor for glucose data is a standard Bluetooth Low Energy (BLE) connection. Mutual authentication is performed between the Receiver and Sensor during the pairing process using application certificates, preventing unauthorized devices from connecting to the Sensor. The transmitted data is protected by encryption. This prevents unauthorized devices from accessing the data if they are within range and intercept the transmission. Under normal operation, the industry standard BLE protocols allow for many users to be in the same vicinity. In the case where the connection is lost due to out-of-range or interference, only the authenticated Receiver that is paired with the Sensor will be able to reconnect and receive glucose data. For apps, only apps logged into the same LibreView account that activated the Sensor are able to complete pairing with the Sensor. For Readers, only the Reader that activated the Sensor is able to complete pairing with the Sensor.

Quality of Service (QoS):

QoS for the FreeStyle Libre 3 Reader and Sensor wireless communications using NFC (for Sensor activation) is assured when the Reader is brought near the Sensor. The communication for activation is specified to occur within 15 seconds.

QoS for the Reader and Sensor wireless communications using BLE for normal operation (receiving glucose readings and alarms) is assured at regular 1-minute intervals. If connection is lost between the Reader and Sensor for 5-minutes, the Reader will display an indication of "Signal Loss" on the results screen. If connection is lost for 20 minutes, the Reader alarms the user if the alarm is turned on. If connection is lost between the Reader and the Sensor, all lost glucose data will be automatically retrieved when the connection is restored. The Reader is designed to only accept BLE data from recognized and paired Sensors. The transmission range for BLE communication is 33 feet unobstructed. If the Reader and Sensor are seeing frequent signal loss at longer distances, bring them closer together.

QoS for the FreeStyle Libre 3 app and Sensor wireless communication using NFC (for Sensor activation) is assured when the phone is touched to the Sensor. The communication for activation takes place within 1 second. If the expected response is not received, the phone will continue to retry.

QoS for the FreeStyle Libre 3 app and Sensor wireless communications using BLE for normal operation (receiving glucose reading and alarms) is assured at regular 1-minute intervals. If connection is lost between the App and Sensor for 5-minutes, the App will display an indication of “Signal Loss” on the Home Screen. If connection is lost for 20 minutes, the App alarms the user if the alarm is turned on. If connection is lost between the Sensor and the App, all lost glucose data will be automatically retrieved when the connection is restored. The App is designed to only accept BLE data from recognized and paired Sensors. The transmission range for BLE communication is 33 feet unobstructed. If the phone and Sensor are seeing frequent signal loss at longer distances, bring them closer together.