Quell will no longer be available without a prescription after September 30. Quell Update Notice

Quell 2.0 Specifications

Looking for all the details you can handle? You’ll find them right here.

Quell Device



1 stimulator (2-lead)


Biphasic with alternating lead phase, asymmetrical, rectangular

Regulated Current or Voltage


Net Charge per Pulse

Nominally 8 µC into 500Ω per pulse; nominally 0 µC per sequential pair of pulses; zero net current

Maximum Output Voltage (±5%)

118 V

Maximum Output Current (<1KΩ load) (±10%)

100 mA

Pulse Duration

380 µsec (includes inter-phase delay)

Pulse Frequency (±4%)

60-100 Hz, randomly varying, 30-50Hz randomly varying, or 120-200Hz randomly varying

Pulse Pattern


Maximum Phase Charge

18 µC

Maximum Current Density (r.m.s.)

0.85 mA/cm2 into 500Ω load

Maximum Average Current

5.6 mA into 500Ω load

Maximum Average Power Density

10 mW/cm2 into 500Ω load

Maximum Pulse Energy (pulse duration < 0.1s)

3.3 mJ per Pulse

Output Trips

No Load

Device not connected to patient

Insufficient Charge

Delivered charge below target

Over Load

Delivered charge above target

Electrode Peel

Electrode dislodging from skin

Therapy Session


60 or 30 minutes

Start Stimulation

Via mobile app Control or automatically upon placing of device on leg

Halt Stimulation

Via mobile app or two taps to the enclosure within 1.5 seconds (double-tap)

Intensity Increase/Decrease

0.5 – 2 mA/sec

Habituation Compensation

Stepwise increase in intensity of 0.3%/min during session

User Interface


Ability to recognize double-tap to the enclosure for stimulation halt

Mobile App

Mobile App control to calibrate, therapy start, stimulation halt, and, intensity adjustment


Micro USB B socket for charging


1 white, 1 orange


Device supports Bluetooth LE 4.2




Cutaneous electrode, disposable


Conductive hydrogel, PET, silver

Number of Electrodes

Four pads, configured as two electrically connected pairs


Male snap


Skin contact area: 33 cm2 inner pair, 28 cm2 outer pair
Exterior: 0.2 cm x 5.3 cm x 28.3 cm




Permanent rechargeable battery

Battery Type

Rechargeable 3.7V Lithium-Ion battery

Charging Source

AC line adapter

Line Current Isolation

Patient disconnected when charging

Patient Leakage Current, DC

<10 μA

Patient Leakage Current, Enclosure

<100 μA



9.4mm x 51.4mm x 77.4mm




IP Classification


Operating Temperature Range

5° C to 35° C

Operating Atmospheric Pressure Range

70 kPa to 106 kPa

Operating Relative Humidity Range

15% to 93%

Transport and Storage Temperature Range

-25° C to 70° C

Transport and Storage Atmospheric Pressure Range

70 kPa to 106 kPa

Transport and Storage Relative Humidity Range

10% to 93%

Guidance Documents & Standards

IEC 60601-1

Medical Electrical Equipment Part 1: General requirements for basic safety and electrical performance

IEC 60601-1-2

Electromagnetic disturbances – requirements and tests

IEC 60601-1-11

Requirements for medical electrical equipment and medical electrical systems used in the home healthcare environment

IEC 60601-2-10

Particular requirements for the basic safety and essential performance of nerve and muscle stimulators

ISO 10993-1

Biological evaluation of medical devices


Radiated and Conducted Emissions Standard for Industrial, Scientific, and Medical (ISM) equipment

ETSI EN 301-489-1, -17

Electromagnetic compatibility and Radio Spectrum matters for Radio Equipment


The Bluetooth word mark and logos are owned by the Bluetooth SIG, Inc. and any use of such marks by NeuroMetrix, Inc. is under license.

Communication between the Quell device and the Smartphone is via Bluetooth.

Disabling Bluetooth

If Bluetooth is disabled on your smartphone or tablet, then the Quell Relief app will not function. Your Quell device will only function if you have previously enabled Automatic Start within the app.

Bluetooth Specifications

Bluetooth Pre-Qualified Design:

Nordic nRF52832 4.2 Low Energy

FCC Rules:

Part 15C



The Quell Relief app requires iOS 10 or later, or Android 6 or later.
iOS and Android devices must have Bluetooth Low Energy (LE, also called Bluetooth Smart) compatibility.