What is the difference between NP (Negative Potential) of Ereada® BROWN mats and AIR ION of Ereada® PURPLE and GRAY mats?

All Ereada® mats generate negative ions when they are heated or when they use your body heat. Negative ions are produced by the anion layers and crystals inside the mat.

If you press the “Air Ion” button on large Ereada® mats, the system uses pulsing and oscillating technology to convert low voltage into high-voltage DC. This creates a controlled corona discharge that releases large numbers of electrons into the air. These electrons are quickly captured by oxygen molecules (O₂), forming negative ions. This process is similar in principle to how negative ions are formed in nature during lightning and storms.

If you press the “Negative Ion” or “Negative Potential” (NP) button on all Brown Ereada® mats or on Gemstone Ereada® Mini mats with NP, the system works in a related way. At the final stage, about 600V DC is delivered to a special silver-fiber layer inside the mat. This creates a negatively charged electrostatic field across the mat surface. Although the voltage is high, the current is extremely low, comparable in power to two AA batteries.

Ereada® Brown mats allow the NP function to work together with heating. The recommended setting is low relaxation levels, such as Levels 1–3 or about 30–50°C. Richway biomats, by comparison, allow their EDNI function only when heating is turned off.

You can activate this feature using the “ION” or “NP” button. Since 2017, a Negative Potential system has been installed on Brown and Gemstone Ereada® Mini mats equipped with the Q2000NP controller.

While regular heated stone mats emit ions mainly through the air or near the skin, the Negative Potential system creates a wide electrostatic field around the mat surface. This surrounds the body with a negatively charged environment during use.

NP is generally considered more penetrating than standard air ionization, which mainly affects the air near the surface. NP sessions run automatically for about 1 hour on standard mats and about 30 minutes on Mini mats, after which they shut off automatically.

This function can be used with or without heat, but gentle temperatures are recommended for comfort.