Due to the ongoing severity of the COVID-19 epidemic, we are temporarily suspending our operations. While we will not be accepting any orders or returns, we are available to assist current customers as needs arise.

This was not an easy decision, however we have always held a strong stance that safety is of paramount priority when it comes to Transcranial Direct Current Stimulation (tDCS). We have gone to extensive lengths to ensure our products are safe, our customers stay safe, and have even blown the whistle when finding other companies selling risky, sub-par tDCS devices. As we monitored the progression of the COVID-19 virus, we quickly realized we would be hypocrites if we ignored the situation.

For the safety of not only our employees and vendors, but our customers and society as a whole, we are suspending operations for now. These are unprecedented times, but we don't have to endure them alone. We are all in this together. From Los Angeles to Beijing, it matters not what your gender is, your race, religion, or economic status... we all can make a difference.

Please, stay home when you can. Practice social distancing, wash your hands often, and BE KIND to your neighbor. And as always, thank you for being a part of The Brain Stimulator Family :)

10 Pack of 3×3″ Replacement Sponges

SKU: Am-Insrt3x3


This 10-pack of 3×3″ sponges are used as replacement sponge inserts for 3×3″ tDCS electrodes.

Over time, electrode sponges lose their integrity, leading to uneven current distribution and less effective tDCS sessions. In addition, using degraded sponges can sometimes cause tingling or itching sensations, especially during the start and end of tDCS sessions.

We usually recommend that electrode sponges be replaced every two weeks, or once every seven tDCS sessions. However, the best results can be obtained by using fresh sponges for each session.


Compatible with: 3×3″ Amrex Sponge Electrodes

*Amrex Rubber Electrode not included


3×3″ Replacement Electrode Sponges

These 3×3″ sponge inserts are used to replace the original sponges that come within 3×3″ Amrex Sponge Electrodes. Additionally, these sponges can be used by themselves as makeshift electrodes by using our Alligator Clip Electrode Cable (or Alligator Clip Adapters if you have one of our older products).

Over time the sponges within Amrex electrodes can grow brittle and crumble, crack, or split causing an uneven distribution of current, reducing the effectiveness of tDCS. Additionally, worn-out sponges can cause an uncomfortable tDCS session, with increased tingling, itching, and sometimes mild stinging sensations occurring. Therefore, it’s a good idea to replace your sponges regularly to ensure your electrodes function properly.

Through our own real-world testing, we have found that it is best to replace tDCS sponges after two weeks, or every 7 tDCS sessions. However optimal results can be obtained by using new sponges for each session.

Additional information


Sponge Size

3×3 inches

Compatible with:

3×3" Amrex Sponge Electrodes

Country/Region of Manufacture