Review: Princeton Tec Byte

The Byte is Princeton Tec's latest entry into the head lamp market. Click to enlarge.

Smaller and lighter is almost always better when it comes to items that you have to carry during your outdoor pursuits and the new Princeton Tec (PT) Byte is certainly smaller and lighter than most head lamps. While it may be short on weight and size, it is definitely not short on function or features. Thanks to advances in LED technology, this tiny power house outclasses many larger head lamps.


  • LEDs: 1x white “Maxbright” LED, 1x red “Ultrabright” LED
  • Weight: 64 grams
  • Battery: 2x AAA batteries
  • Modes: red (Ultrabight), low white (Maxbright), high white (Maxbright)
  • User Interface: Click once for red, click again for low white, click again for high white, click again for off. The Byte must be cycled through all modes to be turned off.
  • Output: 35 lumens on high
  • Runtime: 146 hours in red mode, 96 hours in low white mode, 80 hours in high white mode
  • Price: $20

The Good

There is a lot to like with the Byte. The most obvious is the size and weight. Small and lightweight is the whole point of the Byte. This head lamp is truly small. It has to be held in your hand to truly appreciate how small it is. It is barely wider and longer than the 2 AAA batteries that power it. It is light enough that you will easily forget that you are wearing it and that is with alkaline batteries. Swap in some lightweight lithium batteries and the Byte will probably blow away in a light breeze. There are smaller head lamps on the market but they use coin or button cell batteries. The Byte is powered by inexpensive and easy to find AAA batteries. The larger capacity of AAA batteries versus button or coin cells allows the light to run longer at higher outputs.

The Byte is smaller than the Quad Tactical and most other head lamps. Click to enlarge.

The Byte is smaller in just about every dimension. Click to enlarge.

My favorite feature of the Byte is the red “Ultrabright” LED mode. The Byte’s red mode is very dim and it’s perfect. Most lights have “low” modes that are far too bright. A low mode should provide just enough light for reading a map or navigating a dark room without destroying your dark adjusted vision. The Byte does just that. It is the low mode that I have been wanting for years.

The white “Maxbright” LED has two modes – low and high. The low is more than enough light for most tasks like pitching a tent in the dark or cooking in camp. The high mode is surprisingly bright for such a diminutive light. It works well for those times when you need to see a little further up the trail.

The beam shape of the “Maxbright” modes is very good. There is a wide bright hotspot in the center that provides a fair amount throw. The hotspot tapers smoothly to a wide, bright spill beam that provides broad coverage. The beam shape is very well balanced for a variety of tasks and situations. The Byte’s tiny 3mm “Ultrabright” red LED provides a very wide beam with very few of the dark rings that seem to plague other red LEDs. It is extremely usable.

The switch is relatively large and easy to operate even with gloves on. The bottom of the Byte features a small area of texture that helps you get a grip on such a small light to aim it. The light clicks positively into each position in its arm bracket and can be aimed up or down to suit the user’s preference. The head band is smaller than on most Princeton Tec head lamps but it still retains the handy tool on the slider that makes it easy to open the Byte’s battery latch even with cold hands.

The Byte's switch is large and easy to use. Click to enlarge.

The Byte has a textured area on the bottom that helps the user grip the light to aim it. Click to enlarge.

The Byte head strap is thinner than most Princeton Tec head straps (shown with Quad Tactical strap). Click to enlarge.

The Byte retains the clever tool on the head band that helps open the battery compartment in spite of its smaller size. Click to enlarge.

The light itself seems very sturdy like any other Princeton Tec head lamp. It would make a good primary head lamp for less serious pursuits (camping, hiking, etc) and a great back up head lamp for pursuits that require a head lamp like caving. It would also make be the ideal head lamp to toss in your briefcase or the glove compartment of your car.

I should also note that the documentation that comes with the Byte is big improvement over what usually comes with other lights (including past Princeton Tec offerings). It contains information about how Princeton Tec measures their light’s runtime. Other companies are not usually forthcoming with this information which makes comparing lights very difficult since there are many ways to measure runtime. Princeton Tec also provides a handy chart on the packaging of the Byte that shows the distance at which the light is useful after set periods of time. This information gives you a tangible idea of how the output dims over time. I wish more light manufacturers would provide this sort of useful data.

Princeton Tec provides useful data about the runtime and output on the Byte's packaging. Click to enlarge.

The Bad

I have one nit to pick with the Byte. It is good that it turns on in low red mode. This is great because it helps to preserve the dark adjusted vision of the user. However, the light must be cycled through the low and then high white settings to turn it off. Even this quick exposure to bright white light will ruin your dark adjusted vision. Having to cycle through the brighter white settings basically defeats the purpose of the phenomenal low red setting.

Most of Princeton Tec’s other headlamps have a different user interface (UI) that allows the light to go straight from any setting to off with a press of the button after the light has been in that setting for a few a seconds. If Princeton Tec were to implement a similar UI on the Byte, it would be the closest thing to head lamp perfection that I have ever used.


The Byte is much more than just a back-up head lamp. It is a small headlamp that is as fully functional as much larger head lamps. It is both large enough and small enough at the same time. It has the best low red mode of any light, head lamp or otherwise, that I have ever used. It isn’t perfect but it begs the question… Why buy or carry anything bigger, heavier, or more expensive?

wordpress hit counter


7 Responses to Review: Princeton Tec Byte

  1. zach November 5, 2010 at 17:30 #

    This is a great Light. I got a good deal so I ordered three at your recommendation. I have other head lamps but I honestly will have these in all my gear and do not see much reason for my old, larger lamps with seperate battery packs. I was worried about the brightness. These are plenty bright and the red is just the right brightness.

    It is so light and comfortable I keep one by the bed so I can read without disturbing the wife at night.



    • zach November 5, 2010 at 17:33 #

      PS, If I have to turn it off from low red mode I put one thumb over the lens while I cycle through. Not perfect I know, but it works. PT should strongly consider a slight change which in my view would make this the best headlamp I have used and own. (it really already is)


    • matthewdanger November 5, 2010 at 18:06 #

      I’m glad you like it Zach. I think PT really hit this one out of the park.

  2. Greg Petliski February 17, 2011 at 20:36 #

    I agree with the OP in that even a second of bright light can ruin nightvision. I plan on merely closing my eyes while cycling to off.

  3. Tim March 28, 2011 at 12:33 #

    I like this lamp too but it has a giant weak spot – when the batteries get low it starts strobing at an unusable intensity and refuses to turn off until you take the batteries out. changing the batteries is the only way to fix it and it is temporary at best. It is also a problem that I’ve seen mentioned in more than one product review. I’ve emailed the company about this but haven’t heard back from them.

    • Matt March 28, 2011 at 15:42 #

      I haven’t experienced that yet but I tend to change my batteries proactively. I will run a test tonight and see what happens.

      • Matt March 30, 2011 at 16:44 #

        You are correct. I was able to replicate the flashing effect that you are talking about but I think it is just an annoyance.

        On one hand, the strobing should prolong what little battery life you have, which is a positive. It also lets you know it is time for new batteries (if the significant dimming didn’t clue you in first). However, it is a pain that the light can’t be turned off once it starts to strobe but removing the batteries (if you don’t have fresh ones to install) seems to work.

Powered by WordPress. Designed by Woo Themes