Being an avid runner (both road and trail) and lighting enthusiast, I've owned my fair share of headlamps and running lights over the years and I'm always in search of new and/or different lights for my excursions. I've recently started paying more attention to the Nitecore range and was curious to see how their headlamps would perform, specifically for trail running usage. Nitecore kindly provided me with a NU20, targeted specifically at trail runners. I've put the NU20 through the paces for the past 3 weeks, running with it during some training runs on road as well as some very technical, and in some cases very long trail runs in rain, gale force winds and some intense heat and humidity. Basically, I tried to put it through anything a trail run could. Below is the retail packaging, the headlamp unit itself and the included headband, a very good quality USB cable (only for charging) and user manual. What struck me the most when unpacking was just how tiny this headlamp is.
Nitecore stating the built in 600mah Li-ion battery is equal to the 3*AAA power source found in many headlamps on the market, thus: 2.22Wh vs ~3.5Wh (3*AAA Energizer Lithium@1A) vs ~1Wh (3*AAA Duracell Ultra Power @1A) as per HKJ's reviews. Since the NU20's battery is built in I have no way of testing its capacity without opening it (and possibly breaking it) but I suspect it should reach its claimed 2.22Wh given its approximate physical size. The claimed 6-hrs run time on High seems very suspect but with the ANSI testing method, it's probably correct.
Modes are nicely spaced although I would've liked another mode between medium and high, say a 120Lumen mode. The beam pattern is very nice: a good wide spill and a nice "medium" hot spot. The 2 special modes (SOS and beacon) is a welcome addition especially for a trail running headlamp.
Control:
Low, 1 Lumen (Not noticeable in the photo but very handy for digging around in a backpack):
Medium, 40 Lumens (Not very useful for running on the trails, but OK for walking and some additional light when on the road):
High, 220 Lumen (the only mode that's really suitable for running):
Boost, 360 Lumen for 30 seconds at a time (not much brighter than "high" to the naked eye):
There is an added function that give you an indication of how much battery life is still left. To access this feature, you press the button for 1 second and tiny red light flashes underneath the switch rubber. 3 Flashes=above 50%, 2 flashes=bellow 50% and 1 flash=less than 10%. Managed to capture the blink:
A very good quality elastic headband adjusts with ease. The switch guard is a very welcome addition as I had a headlamp switching on inside my hydration pack before and the ability to charge the headlamp on-the-go is also a very nice addition. The plastic casing helps with the weight and I never found the casing get too hot to the touch, even on my hottest most humid run. The rubber switch cover, waterproof seal on the USB port and the tightly glued(?) casing kept the rain out, no problem. I only submerged the NU20 in the basin (roughly 20cm of water) for a good 30mins and no signs of a leaks. So for "normal" trail running use, it will hold up just fine during a HEAVY downpour as well as getting soaked from sweat in a hydration pack or shorts.
Speaking about shorts: It's compact size and light weight meant I could very easily bunch it up and stuff it into my back pocket on my shorts if I knew I was going to, or planning on running in the dark for the last part of my run. This is where I think that the headband could be much thinner as the light weight of the headlamp doesn't need a very strong elastic band to keep it in place. Bunching or rolling it up saw most of the bulk came from the strap.
Size comparison to a Petzl Tikka RXP and the HC30:
The fact that the battery is built-in and I have no way if replacing it or carry a spare is a bit of a negative, however by the time the battery has done its 300 or 500 cycle it would probably be 1,2 maybe 3 years later and you'll have upgraded to a NU20(ver2) already. The swivel "click" is very sturdy, perhaps too sturdy as you have to use both hands if you want to adjust the angle. Personally, the UI is a bit annoying for me, turning on and switching up modes is an easy click however, the mode cycle grates me. From switching the light on to Low, you have to click again within 3 seconds if
you want to cycle to medium or high, after 3 seconds a "click" will turn the light off. So if I do a trail run and I reach a long steep hill mid-way and I want to switch from High to Medium (to conserve the battery and as I don't need 220 Lumens for this slow pace) the light will turn off and I then have to turn it on again and then cycle to medium. And then switching from medium to high as it gets darker and I need more light, for that few seconds from turning off to back again and cycle to high means I have to stop, do the switching dance and then get going again…it's annoying.
I found the High mode only gives you 1h10mins of usable light, after that there is a very sharp drop in light output. I've reproduced and confirmed this result later with lux meter also. So for proper usage the NU20 is perfect for roughly 1 hour of running, on high mode that is. I've not testedruntime on medium though as 40 Lumens is not nearly enough light for night running, in my opinion anyways. So I judge and review this headlamp purely based on its performance on "High". Personally I don't like Lumens as a unit of measure for any light (headlamps or hand held) intended for running use and I really wish manufacturers would start publishing Lux values at various distances up to 15m preferably. As we all know 1000lumen means nothing if it's not managed and directed properly, i.e. reflectors, lenses etc. Running on trail at night requires a well illuminated area for sufficient view of the terrain and obstacles and this is where ANSI figures fall flat on the face. 6-Hrs ANSI run time is useless if usable Lux is provided for only a fraction of that time. The addition of the on-the-go charge feature gives the NU20 a comeback for longer use, although the USB port is in completely the wrong place for this. Inserting the USB cable into the port and routing the cable to a hydration vest or shorts pocket to connect it to a small battery bank means the cable is in clear obstruction of my left eye…HUH!? The most obvious place for the USB port for on-the-go charging is surely in the side of the casing. Unless I'm missing something here?
Some points:
Weight: 5/5 (extremely light, could lose some more weight with a thinner headband)
Brightness: 3/5 (bright for its size, but lacking some serious turbo)
Run time: 1/5 (enough for a short run, but not nearly enough for a more serious night run)
Comfort: 5/5 (barely noticeable on your head)
Innovation: 4/5 (some nice features but docking a point for the position of the USB port)
In Total: 18/25
In conclusion, the NU20 is a very welcome addition to the Trail running scene and even for training runs on the road. IMHO this really is the perfect everyday headlamp for any runner spending up to 1hour in the dark, road or trail. To my surprise, the NU20 has knocked my current favourite, my Petzl Tikka RXP to the drawer for the majority of my runs. It's not without its limitations though: usage past the 1hour mark means you'll have to carry a battery bank to charge it with if you don't mind having your left eye obscured by the USB cable.
Nitecore stating the built in 600mah Li-ion battery is equal to the 3*AAA power source found in many headlamps on the market, thus: 2.22Wh vs ~3.5Wh (3*AAA Energizer Lithium@1A) vs ~1Wh (3*AAA Duracell Ultra Power @1A) as per HKJ's reviews. Since the NU20's battery is built in I have no way of testing its capacity without opening it (and possibly breaking it) but I suspect it should reach its claimed 2.22Wh given its approximate physical size. The claimed 6-hrs run time on High seems very suspect but with the ANSI testing method, it's probably correct.
Modes are nicely spaced although I would've liked another mode between medium and high, say a 120Lumen mode. The beam pattern is very nice: a good wide spill and a nice "medium" hot spot. The 2 special modes (SOS and beacon) is a welcome addition especially for a trail running headlamp.
Control:
Low, 1 Lumen (Not noticeable in the photo but very handy for digging around in a backpack):
Medium, 40 Lumens (Not very useful for running on the trails, but OK for walking and some additional light when on the road):
High, 220 Lumen (the only mode that's really suitable for running):
Boost, 360 Lumen for 30 seconds at a time (not much brighter than "high" to the naked eye):
There is an added function that give you an indication of how much battery life is still left. To access this feature, you press the button for 1 second and tiny red light flashes underneath the switch rubber. 3 Flashes=above 50%, 2 flashes=bellow 50% and 1 flash=less than 10%. Managed to capture the blink:
A very good quality elastic headband adjusts with ease. The switch guard is a very welcome addition as I had a headlamp switching on inside my hydration pack before and the ability to charge the headlamp on-the-go is also a very nice addition. The plastic casing helps with the weight and I never found the casing get too hot to the touch, even on my hottest most humid run. The rubber switch cover, waterproof seal on the USB port and the tightly glued(?) casing kept the rain out, no problem. I only submerged the NU20 in the basin (roughly 20cm of water) for a good 30mins and no signs of a leaks. So for "normal" trail running use, it will hold up just fine during a HEAVY downpour as well as getting soaked from sweat in a hydration pack or shorts.
Speaking about shorts: It's compact size and light weight meant I could very easily bunch it up and stuff it into my back pocket on my shorts if I knew I was going to, or planning on running in the dark for the last part of my run. This is where I think that the headband could be much thinner as the light weight of the headlamp doesn't need a very strong elastic band to keep it in place. Bunching or rolling it up saw most of the bulk came from the strap.
Size comparison to a Petzl Tikka RXP and the HC30:
The fact that the battery is built-in and I have no way if replacing it or carry a spare is a bit of a negative, however by the time the battery has done its 300 or 500 cycle it would probably be 1,2 maybe 3 years later and you'll have upgraded to a NU20(ver2) already. The swivel "click" is very sturdy, perhaps too sturdy as you have to use both hands if you want to adjust the angle. Personally, the UI is a bit annoying for me, turning on and switching up modes is an easy click however, the mode cycle grates me. From switching the light on to Low, you have to click again within 3 seconds if
you want to cycle to medium or high, after 3 seconds a "click" will turn the light off. So if I do a trail run and I reach a long steep hill mid-way and I want to switch from High to Medium (to conserve the battery and as I don't need 220 Lumens for this slow pace) the light will turn off and I then have to turn it on again and then cycle to medium. And then switching from medium to high as it gets darker and I need more light, for that few seconds from turning off to back again and cycle to high means I have to stop, do the switching dance and then get going again…it's annoying.
I found the High mode only gives you 1h10mins of usable light, after that there is a very sharp drop in light output. I've reproduced and confirmed this result later with lux meter also. So for proper usage the NU20 is perfect for roughly 1 hour of running, on high mode that is. I've not testedruntime on medium though as 40 Lumens is not nearly enough light for night running, in my opinion anyways. So I judge and review this headlamp purely based on its performance on "High". Personally I don't like Lumens as a unit of measure for any light (headlamps or hand held) intended for running use and I really wish manufacturers would start publishing Lux values at various distances up to 15m preferably. As we all know 1000lumen means nothing if it's not managed and directed properly, i.e. reflectors, lenses etc. Running on trail at night requires a well illuminated area for sufficient view of the terrain and obstacles and this is where ANSI figures fall flat on the face. 6-Hrs ANSI run time is useless if usable Lux is provided for only a fraction of that time. The addition of the on-the-go charge feature gives the NU20 a comeback for longer use, although the USB port is in completely the wrong place for this. Inserting the USB cable into the port and routing the cable to a hydration vest or shorts pocket to connect it to a small battery bank means the cable is in clear obstruction of my left eye…HUH!? The most obvious place for the USB port for on-the-go charging is surely in the side of the casing. Unless I'm missing something here?
Some points:
Weight: 5/5 (extremely light, could lose some more weight with a thinner headband)
Brightness: 3/5 (bright for its size, but lacking some serious turbo)
Run time: 1/5 (enough for a short run, but not nearly enough for a more serious night run)
Comfort: 5/5 (barely noticeable on your head)
Innovation: 4/5 (some nice features but docking a point for the position of the USB port)
In Total: 18/25
In conclusion, the NU20 is a very welcome addition to the Trail running scene and even for training runs on the road. IMHO this really is the perfect everyday headlamp for any runner spending up to 1hour in the dark, road or trail. To my surprise, the NU20 has knocked my current favourite, my Petzl Tikka RXP to the drawer for the majority of my runs. It's not without its limitations though: usage past the 1hour mark means you'll have to carry a battery bank to charge it with if you don't mind having your left eye obscured by the USB cable.
Last edited: