Battery or Mains?

This is an easy one when browsing ElectraStim units. Our SensaVox unit (which is over a decade old) is the only one of our powerboxes that has the option of mains power. 

All the rest of our stimulators are now powered by fully rechargeable internal batteries which have a high capacity, long life span and are much better for the environment than disposable or replaceable batteries. Every stimulator is packaged with a USB cable that can be used with any phone charger or port on a laptop or computer for quick and easy charging. 

Our flagship stimulators Flux and AXIS have not only succeeded SensaVox in terms of features but they also boast an identical top power level just with a rechargeable internal battery instead of a mains cable!

Power/Intensity Levels

Electro stimulation can run the pleasure spectrum from light tickles and tingles to intense throbbing and clenching sensations that some people might feel too intense!

Choosing your power level does depend on how hard you usually like to play and whether you're likely to experiment with our largest accessories. For complete beginners, we'd recommend starting with KIXFlick or Flick Duo- our three lowest output stimulators. These all have a wealth of functions and patterns but their top intensity is nowhere near the level of sensation SensaVoxFlux or AXIS can deliver.

Your budget is also important- the higher end stimulators are an investment whereas our lower power units are much more affordable if electro is something you want to use occasionally. Our Single Output Beginner unit KIX is an ideal introduction to electro at a price that doesn't break the bank.

However, if you feel as though electro is going to be something you enjoy and experiment with a lot then we highly recommend purchasing one of the 3 top level stimulators that your budget allows. This gives you room to experience a full range of intensities and means that your stimulator will be compatible with all our accessories. The larger the toy, the more power it needs to really get the full experience!

Single or Dual Output/Channel?


  • Cost effective
  • Lower maximum intensity i.e. ideal for beginners
  • Simple range of play modes 
  • Ideal for solo play or connecting to just one partner at a time
  • Can power a maximum of 2 x unipolar toys (i.e. pads) or 1 x bipolar toys (i.e. silicone items like dildos)
  • USB Rechargeable


  • Feature-rich
  • More expensive 
  • High Maximum Intensity 
  • Wide variety of play modes, patterns and input methods (i.e. controlling it with music!)
  • Can power a maximum of 4 x unipolar toys or 2 x bipolar toys - ideal for couples where both partners want to play at different intensities
  • USB Rechargeable (except our legacy unit SensaVox which is powered via a mains cable or 9V battery)

You can filter our stimulators by whether they're Single or Dual output in the sidebar of our online catalogue.

The bottom line is that if you intend to play with a partner that a Dual Output stimulator is really the only way to go. More often than not one partner likes a more intense experience than the other- a Dual Output stimulator will let you both play together at an individual, comfortable level.

Stimulator Comparisons & Compatibility

Our handy comparison table will give you all the technical information you need about each stimulator.

To find out which toys are compatible with which stimulators, visit our Compatibility Table.

Warning: Not All Electro Is Created Equal

This is a bit techie but important information to know.

There are potentially hundreds of different 'e-stim' or 'TENS' devices on the market but the truth is that only a couple of specialised electro sex brands (of course that includes us!) take the time to make sure their stimulators are pleasurable, effective and SAFE. The adult toy market isn't widely regulated so it's important you can trust a manufacturer to have your best interests at heart.

When purchasing an electro sex stimulator it's imperative that the manufacturer is able to give you answers about all the points below so you can make an informed choice.

ALL ElectraStim devices are designed with our medical background in mind and are 100% compliant with all of these safety recommendations:

Are ElectraStim Toys Compliant?
Consistent Output Intensity

If you intend to use your stimulator with a partner it is important to know their stimulation intensity limits so as to keep play friendly, assuming that’s your intention! You can only do this effectively if the intensity range, from 0% to 100%, is stable across the entire battery level range otherwise the intensity level value will not always represent the same output intensity. Even if you are playing solo you do not want to have to keep increasing the intensity as the battery is dying.

Output Intensity Linearity

This basically means if your intensity level setting says you are on 50% then you should of course be at around half way to maximum. For instance, some stimulators might say that you are at 50% whereas in fact you are more like at 90%. This means that for the remaining 50% of adjustment you will feel only 10% difference in intensity.

Interpolated/Interleaved Outputs

When using a dual output (2 channel) stimulator with both outputs being used it is important that there is no cross-channel interference. For instance, if a butt-plug accidently came out during play you would not want to get a large current surge to your cock rings – ouch! If the outputs are actively driven at exactly the same point in-time, then this is exactly what happens as a portion of current is effectively diverted from one channel to the other. Similarly, if you increase the power to the butt plug, the power in the cock ring will simultaneously decrease, meaning that you constantly have to compensate. Preventing this is achieved by ensuring that the output pulses are never actually active at the same time, but to the user it will feel like they are due to the relatively high frequency.

Zero Net DC Current

In order that nerves can recover or re-polarize it is important that the simulation waveform returns to zero volts between pulses. At higher stimulation frequencies, typically above 500Hz, the transformers used to generate the stimulation pulses do not have time to recover and hence a DC (direct current) potential is created. This should not be allowed to happen in medical TENS devices as this would be referred to as a patient leakage current which has an upper limit of 10 micro-amps. However, most bespoke stimulators on the market do not care about the medical safety requirements as they are not registered medical devices.

Non-exposed Stimulator Connectors

Some stimulators on the market use exposed metal type connectors, a typical example being audio style jack plugs. Although unlikely, it is possible for this exposed pin to be inserted into a mains power socket whilst connected to attached or inserted electrodes. For extra safety, fully shrouded plugs are advisable for stimulator connection. Again, TENS machines should comply as this is a medical safety requirement.

Hi-Flex Output Cables

To ensure you get maximum life from your output cables (the cables that connect your stimulator to your chosen accessory/electrode) ensure that your stimulator is supplied with hi-flex cables. These are often called Tinsel Wire Cables due to their construction which incorporates a fabric cord for tensile strength and has copper threads running through it.

Responsive Intensity Controls

For reasons of comfort it is important that you have full control over the stimulation intensity level just in case you go a little too high before you are ready. This can typically happen on stimulators with dials (potentiometers or digital encoders) as these can easily get accidentally knocked. It is therefore important that your intensity controls are responsive when turned quickly.

All ElectraStim stimulators will also start at zero intensity, no matter where you left off. This gives you full control over the intensity of the sensations. Lower quality units with dials in particularly can be accidentally knocked to the highest levels before they're turned on. It can be quite an unpleasant surprise to go from 0-100% immediately!

Controlled Low Battery Status

Most modern e-stim devices are controlled by microprocessors which enables many features such as built-in patterns, audio processing etc. However, to function correctly it is mandatory that battery monitoring and a controlled shut-down procedure is implemented to so as to avoid sporadic behavior at the end of the batteries useful life. Some stimulators on the market have their power controlled by mechanical switches and therefore do not have the ability to shut themselves down when the battery and hence microprocessor supply start to “drop-out”. This can give rise to what is known as a brown-out condition which basically means the memory and processor synchronization can be lost and peripheral features will start to fail.

ALL ElectraStim Stimulators abide by all 8 of these safety guidelines and are CE certified.

The quickest way that you can check if a stimulator is safe to use is to check whether it has got a CE approved marking. Cheaper stimulators without this marking have often not been appropriately safety tested.

If you are ever in doubt when making a purchase it's always best to double check- especially if you're new to electro stimulation.