Yes, you could.
Please keep in mind that the primary work done by the cold laser is based on the actual wavelength of light emitted (650 nm).
The frequency we use to drive it is auxiliary and can afford additional benefits.
Use of the cold laser shows that usually 30m of exposure is all that it takes to effect maximum efficacy. After this you can continue exposure, but the body doesn't really show the same level of change as it would the first 30 minutes.
Wearing two devices would just shorten the time before you get to that point.
Blood flows typically through the body fully within a minute or two. So over that 30m with one wrist unit on, you entire blood supply is exposed between 15 and 30 times.
When using a frequency, the slower frequencies work better than the higher frequencies, as the frequency governs how fast the laser is turned on and off.
Very high frequencies would turn it on and off so fast it would never get a chance to fully turn on, and the output will be diminished.
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