Spazer & SAIDI Red Light Comparison

Battery Power

  • frees the user from the wire

  • is practically zero EMF

You can purchase any cell phone battery bank to convert the Spazer into a battery-powered light.

The SAIDI comes with the battery installed.

Battery Powered



Battery Life

Depends on charger

60 to 90 minutes

USB Power

  • tethers the user to the wire

  • is practically zero EMF

Plug the cord into a USB power source to run the light.

Use the power adapter and cord to charge the light. Use the battery to run the light.

USB Powered



Wall Outlet Power

Outlet Powered



  • tethers the user to the wire

  • good transformers are low EMF; bad ones emit unwanted EMFs

Obtain a low-EMF and USB-to-AC adapter according to page's instructions.  Allows you to run off wall power instead of USB. 



Red 630 nm



Red 660 nm



Infrared 850 nm




  • If vendor uses solar meter to measure LED power density, the real value is less than half the claimed value.

  • If vendor relies on manufacturer's power density claims, the real value can be significantly less than stated.

  • Power density at zero inches (light pressed to skin) is reliable if tested with a spectrophotometer or LED meter, HOWEVER

  • Power density measured at any distance is vastly overstated due to reflectance

  • For example, if you measure power density at 6 inches with a meter designed to measure LED light, and get 100 mW, then you can say that 100 mW lands on the target surface. But because the skin REFLECTS photons, and because the lamp is not pressed to the skin to blunt reflection, that 100 mW value is drastically overstated. It can be and often is as low as 5 mW/cm^2 when stated as 100 mW/cm^2. 

  • Therefore, a LOW to NO EMF light pressed to the skin is signficantly more powerful than a "powerful" light at 6 inches.

Inches Distance from User 

Power Density mW/cm^2/second

Power Density mW/cm^2/second















Tiny: 0.5%



Tiny: 4 V/m 0.13 milliGauss

Tiny: 4 V/m 0.23 milliGauss




Treatment Area at 0 Inch Distance

3.5 in. x 5 in.

3.5 in. x 5 in.

Typical Lifetime Hours



EMF Channel Rating

Read Review

Buy Light

Best Red Light Therapy Devices

Spazer is a bright light

The Best and Most Powerful Zero EMF Spazer Red Light Therapy Device

Some electromagnetic fields (EMFs) such as light are healthy. Some non-natural EMFs (nnEmfs) such as the fields generated by a ...
Read More
GembaRed SAIDI red light therapy device for EHS (electromagnetic hypersensitive) people

The Best Red Light Therapy for EHS Consumers

The SAIDI Light from GembaRed is one of the only red light therapy devices on the market with no flicker, ...
Read More

Copy Successful Studies Using Recommended Lights

Acne Vulgaris in Women Red Light Dose

Science study Red light therapy skin dose
Decreased acne lesions, decreased skin sebum excretion in women at end of treatment and 3 month followup. Study used multiple ...
Read More

Reduce Herpes Zoster Pain Red Light Dose

Red light therapy virus dose: herpes, shingles, post herpetic neuralgia
633 nm, 50 mW, 2 J/cm^2, 300 second treatments, 3 treatments/week for 1 week reduced post-herpetic neuralgia pain ...
Read More

EMF Channel Categories

Copy a light therapy study time and frequency

Done For You: How to Copy a Light Therapy Study

Find a study you want to copy with your device. Look for your device in our tables. Use the info ...
Read More
Copy successful studies with your light

How to Copy Successful Light Studies with Your Device

Every light therapy device emits specific wavelengths found to have therapeutic value. The studies giving us confidence in those wavelengths ...
Read More
Best EMF Devices

Best Light Therapy Devices

Discover the best red light therapy as well as blue, green and infrared light therapy devices based on quality, testing, ...
Read More
Light therapy of the feet

Light Therapy

"Light therapy" is the use of visible and infrared light to heal ...
Read More
EMFs are healthy and dangerous, depending on the wavelengths

About EMF Channel

Electromagnetic fields (EMFs) are photon waves the surround and penetrate our bodies. They are physical light, a cell phone tower ...
Read More
EMF Spectrum

EMF Science

EMF study, book and article summaries, including cell phone studies harm and light therapy studies ...
Read More
EMF Effects both healthy and harmful

Defense Against Harmful EMFs

A trillion dollar industry has a hugely vested interest in denying that cell towers and phones are harmful to humans ...
Read More
Andrew LaTour testing a red light therapy bed at a biohacking conference

EMF Therapy Pioneers

Meet the pioneers creating healing EMF therapy and protective EMF devices ...
Read More
Red light rhinophototherapy

Light Therapy Studies

All EMF Channel red light therapy articles excluding the therapy dose database entries ...
Read More
EMF Articles

EMF Studies

EMF Studies, Articles, and Books, exploring both the therapeutic and the harmful effects of electromagnetic fields ...
Read More