The Princeton Tec Byte fits the theory that the best emergency gear can be forgotten about until needed. The Byte’s small size makes it easy to tuck into a pocket and the minimal weight makes it completely unnoticeable. It stays unnoticeable during use, with a secure fit and zero bounce. The Byte has two illumination modes—low and high—along with a red LED option. The low setting was too low to really have much use, but the high setting was more than adequate on dirt roads and smooth trail. Of course, the features which make the Byte such a great light, also contribute to its shortcomings.

The Byte is small and lightweight in part because it only uses two AAA batteries, but because it only uses two AAA batteries, the light is not as bright and the battery life is not as long as other lights in the category. The Byte is therefore probably not the best choice for long nights, technical trail, or any situation in which visibility is paramount. The Byte is an excellent choice for running during dawn and dusk, when high levels of illumination are not necessary. It also makes an excellent backup light.

Comfort
The Byte is an extremely comfortable headlamp due to its lightweight. There is essentially no bounce at all, and although the strap is fairly thin, very little tension is needed on the strap to keep the headlamp in place. The result is a light that is barely noticeable.

Brightness
At 70 lumens, the Byte is clearly not the brightest headlamp out there. It is however sufficient for night time running on smoother surfaces including dirt roads, sidewalks, and groomed singletrack, particularly during dawn and dusk. Caution is likely required on anything highly technical, however.

Ease of Use
The Byte is fairly straightforward to use, with a rubber coated button that cycles through the different modes. One minor inconvenience however is that turning off the lamp requires cycling through all of the modes. Some headlamps, when left in one mode for a certain period of time, will reset so that pressing the button again turns the light off instead of switching to the next mode.

Features
The Byte has a basic but useful feature set: spot illumination modes with low and high settings, and a red mode. The Byte also has a battery lockout feature, which adds peace of mind when the light is packed away for later use.

Run time
The Byte has a quoted runtime of up to 96 hours, which is more than enough for a multi‐night fast packing trip. No battery issues were encountered during testing.