This review contains sponsored content. Originally published in German on Geartester.de.
Anyone who hunts in summer knows the problem: the moment the sun goes down, you become a target on the stand, not for game, but for a different plague: mosquitoes. Especially near water or after heavy rain, every sit quickly turns into a test of patience. That’s where the Nitecore EMR25 comes in, a modern mosquito repelling device with a built-in 12,000 mAh battery and OLED display, designed specifically for portable use. I tested it out in the field for you.
The device currently costs 94.95 euros direct from Nitecore, making it pricier than the cheapest devices of this kind, but it comes with a noticeably longer battery life and a few extra features.
The EMR25 in the field
Field use
My test took place at a wildlife food plot between forest and field, a classic mosquito zone, especially after days of rain. The damp surroundings created a genuine mosquito plague. Just minutes after switching on the EMR25, the effect was clearly noticeable: not a single mosquito left in the blind, no annoying buzzing, no bites, and all without any noticeable smell or disruptive noise.
Controls and functions
Operation is pleasantly simple and self-explanatory. Two buttons control the device: one for the ultrasonic mode, the other for the heating wires (choice of “low,” “high,” or “off”). That makes it easy to operate even with gloves on or in the dark. Runtime is hunt ready: with ultrasound and heat on the high setting, the device ran for over 7 hours, and up to 9 hours in the power-saving mode.
Nitecore states a protection range of 3.35 m in low mode and 4.9 m in high mode. That’s supposedly reached after around 10 minutes thanks to a heating temperature of 180°C. The actual size of the protection zone was hard to measure precisely, I think it’s best to just pick the mode by feel. In active mode, the OLED display shows remaining time along with the active mode.
Running it off a different power bank, or even mains power via an outlet, is theoretically possible too. The device should explicitly not be used in enclosed spaces, though.
The housing is IPX5 rated and feels very rugged. Weight comes in at around 300 g.
What’s included: carrying case and a first set of active-ingredient pads
Ultrasound while hunting: yes or no?
The ultrasonic mode operates at 40 kHz, which is outside the range of human hearing, but worth considering around predators, since foxes and similar animals can hear up to roughly 45 kHz. Roe deer and wild boar perceive frequencies up to around 30 kHz. Ultrasound has to be switched on separately though and isn’t active by default, which makes the EMR25 usable for stalking too, depending on the type of hunt and target species, it’s a judgment call.
Refill pads: flexible and cheap
A big advantage of the EMR25 is the flexibility around mosquito repellent pads. By default it uses Nitecore MRM10 pads, which cost around 1 euro each and last around 6 hours apiece. One pad contains 10 g of the proven active ingredient prallethrin. Alternatively, two MRM10 Mini pads can be used at once, also with 10 g of prallethrin each.
Especially handy: the device is compatible with most standard mosquito repellent mats sold commercially. The heating chamber fits either one large pad (34 × 48 mm) or one to two smaller pads (35 × 22 mm). Slightly different sizes are accommodated without issue too, a real plus for restocking on the go or abroad.
Extra value and recommendation
What I particularly like: the EMR25 isn’t just a mosquito repellent, it also works as a power bank. That lets you charge thermal cameras or smartphones on the go when needed. For me, that’s a genuine added value, especially on long sits or in remote parts of the hunting ground with no power.
USB-C output up to 20W and input up to 18W
A tip from the field: don’t do what I did
A small tip on the side: when inserting the pads, make sure to put them in short-side up, in other words, not the way that lets you comfortably read the Nitecore print. Do that and they get stuck in backwards, requiring tweezers, patience, and some quiet cursing to get back out. This, of course, did not happen to me…….
Handy belt clip on the back of the device
For sitting on stand, the Nitecore EMR25 is a clear recommendation. Anyone who sits still for long stretches knows how disruptive mosquitoes can be, and the device provides noticeable relief. For dog handlers or mountain hunters who need to save weight, it’s less of a fit, but as a stationary solution, say around a campfire, at the hunting cabin, or while camping, it’s very practical.
Conclusion
The Nitecore EMR25 is more than just mosquito protection, it’s a well thought out, versatile device for hunters and anyone who enjoys the outdoors and values peace and quiet, functionality, and well designed gear. It’s a genuine win especially on summer evening sits, and anyone who’s ever had a mosquito buzzing right next to, or inside, their ear for hours knows: that’s priceless.
Transparency note: the product was provided to me free of charge by Nitecore for testing. There were, however, no content requirements or conditions on what I should write about it. I receive no payment for this review and am sharing my personal, unbiased opinion.