June 22, 2026

Wavelengths 660nm and 850nm

Behind the Wavelengths: Why 660nm and 850nm?

Different wavelengths of light serve different purposes, so why do we specifically use 660 nanometers and 850 nanometers on all of our Redline products? The wavelengths used in a red light device determine how deeply light penetrates the tissues as well as the cell’s response.

You may know by now, all of our Redline products utilize at least both 660nm (red light) and 850nm (near-infrared light). By combining these two wavelengths, our Redline products are able to balance penetration depth with cellular response to provide support where it matters most.

Why Wavelength Matters

Light therapy delivers specific wavelengths of light into the body’s tissues. Once it has been absorbed, the light interacts with the cells in the stimulated area to support mitochondrial function, circulation, and/or recovery responses.

The mitochondria is a very important part of the cell. Commonly referred to as the “powerhouse of the cell,” this is where ATP, the primary energy source of cellular function, is produced. Research has shown certain wavelengths of light can help to stimulate ATP production which in turn improves cellular efficiency. During exercise, stress is placed on the muscles and soft tissues. Supporting cellular functions by stimulating energy production aids the recovery process,

The Role of 660nm Red Light

660 nanometers is on the visible red light spectrum and is commonly associated with surface-level cellular activity. Research has shown red light can support collagen production, superficial cellular energy production, and aid the recovery process in surface level tissues.

For horses in particular, this can be particularly beneficial for skin issues such as minor cuts/abrasions, hair growth, scratches, blanket rub, and scar healing. In order to stimulate cellular function within deeper tissues, we must look to a different wavelength of light for support.

The Role of 850nm Red Light

850 nanometers, a part of the near-infrared (NIR) spectrum, is capable of penetrating deeper tissues than just the skin. When looking to aid cellular function in the muscles, tendons, joints, and other soft tissues, this is the wavelength you would want to use.

According to The Handbook of Photomedicine, certain NIR wavelengths penetrate tissues more effectively than others. In particular, studies have shown that 850 nm actually penetrates deeper than 940 nm in soft tissue (Ferraresi & Parizotto, 2013), another commonly utilized NIR wavelength. 940 nm is more easily absorbed by water within the body’s tissues, which can absorb and scatter the energy, reducing how deeply the light is able to penetrate (Lee & Kim, 2019).

Both 660 nm and 850 nm utilize metabolic processes in the mitochondria to stimulate ATP production, a function that starts to decrease after about 900 nm. For this reason, 850 is considered the “GOLD STANDARD” in photobiomodulation because it is at the intersection of peak depth of penetration and mitochondrial response.

These are the primary reasons we specifically chose 850 nm for our Redline products. The more reliable deep penetration can help to support the muscles, tendons, joints, and other internal tissues. Whether your horse is recovering from an injury, or simply needs support in recovering from training and competitions, Redline is your go-to.

What This Means For Your Horse

Traveling, training, competitions, and consistent work all create physical stress on your horse’s body. This stress can cause the muscles and soft tissues to experience fatigue, inflammation, and oxidative stress.

Studies have shown incorporating light therapy into your care routine can support circulation, assist cellular energy production, help manage inflammation, and support the overall recovery process. For riders, this translates into a horse that may recover more comfortably between rides, feel less soreness and fatigue after strenuous work, and maintain better consistency throughout training programs.

It’s important to note that light therapy is not a replacement for veterinary care, conditioning, or proper recovery protocols. Instead, it may serve as an additional tool within a comprehensive wellness and performance routine.

The Making of Redline

When developing our Redline products, choosing the wavelengths was one of the most important decisions we made. Creating therapy tools that could support cellular activity in both surface-level and deeper tissues was very important to us.

This philosophy stems directly from the science behind light therapy. Because different wavelengths can influence how effectively light reaches certain tissues and how cells respond; we needed to choose wavelengths that have been widely researched and recognized for their ability to support both cellular activity and deeper tissue penetration.

By combining both 660 nm red light and 850 nm near-infrared light, we are able to balance surface-level support with deep tissue penetration to support recovery and performance throughout the body.

Final Takeaways

The science behind light therapy is ultimately about more than simply shining light on the body or choosing the “bigger” number. Careful wavelength consideration matters because it influences how deeply light penetrates and how effectively cells may respond.

Redline was designed to support the demands placed on the equine athlete, from daily training rides to intense competition schedules while being easy for the rider to use.