Black Diamond Cosmo 350 Headlamp Graphite

I bought this headlamp at the recommendation of one of the folks at the REI store. I had come in looking for a different one and the person recommended. This is having more features in the one I wanted for the same money. My son and I needed headlamps for Boy Scouts because setting up tents on Friday night in the dark is tough with just a lantern or a flashlight that doesn’t allow you to keep hands free. These run on AAA but scan take a rechargeable battery as an upgrade. One of the nicer features is the red led which is just enough to see close without blinding or waking others up at camp. These were heavily used for two nights at the highest setting and they lasted about as long as promised at that setting without battery changes. Changing to the lower setting is ... MoreI bought this headlamp at the recommendation of one of the folks at the REI store. I had come in looking for a different one and the person recommended. This is having more features in the one I wanted for the same money. My son and I needed headlamps for Boy Scouts because setting up tents on Friday night in the dark is tough with just a lantern or a flashlight that doesn’t allow you to keep hands free. These run on AAA but scan take a rechargeable battery as an upgrade. One of the nicer features is the red led which is just enough to see close without blinding or waking others up at camp. These were heavily used for two nights at the highest setting and they lasted about as long as promised at that setting without battery changes. Changing to the lower setting is confusing and we had to reread the directions a few times. But now it is simple. I would definitely buy this again.

The first thing I noticed when I received the Cosmo 350 was the compact packaging with very little plastic. Easy to open and easy to recycle! Another nice touch: the headlamp came with three AAA batteries. On my kitchen scale, it comes in at 80g, it would be 75g if using the optional BD1500 rechargeable batteryI’m impressed with the headlamp’s usability. The light has two buttons, one larger on/off switch, controlling also brightness and steady/flash modes, and one smaller, to toggle between white and red light. Both the white and red lights are dimmable and both can be used in flash mode. Compared to some other headlamps I have used, the controls are very intuitive. Clicking once turns the light on or off, clicking twice switches from steady to flash and simply ... MoreThe first thing I noticed when I received the Cosmo 350 was the compact packaging with very little plastic. Easy to open and easy to recycle! Another nice touch: the headlamp came with three AAA batteries. On my kitchen scale, it comes in at 80g, it would be 75g if using the optional BD1500 rechargeable batteryI’m impressed with the headlamp’s usability. The light has two buttons, one larger on/off switch, controlling also brightness and steady/flash modes, and one smaller, to toggle between white and red light. Both the white and red lights are dimmable and both can be used in flash mode. Compared to some other headlamps I have used, the controls are very intuitive. Clicking once turns the light on or off, clicking twice switches from steady to flash and simply holding the large button adjusts brightness. An added feature is that the last setting used persists when the Cosmo 350 is turned off and on again. As someone who cross country skis early mornings and late nights, I was a little worried that it would be hard to operate the buttons while wearing heavy winter gloves. I tested this and the buttons were easy to push wearing gloves.The Cosmo 350 is comfortable to wear, the wide headband is easy to adjust. I prefer having a third band going over the top of my head while running with a headlamp, but the light weight of the Cosmo makes this likely unnecessary. Dabbling a bit in stargazing and astrophotography, I really appreciate the brightness-adjustable red light to preserve night vision while adjusting camera settings.I was curious how long a charge of Black Diamond’s BD1500 would last. After I topped off the battery in the provided charger, I inserted it and turned on the light on its highest brightness setting at 8 AM. At noon, the light was still bright. Leaving the headlamp on my desk, I forgot about it until around 9 PM. To my surprise, the light, while not as bright, was still on when I checked. One note: when I started this test, I initially carried the light in my pocket and noticed that it got rather warm. After I took it out, the heat dissipated quickly. It may be a good idea to make sure that the Cosmo 350 is off before stashing it away. By the way, there is a locking feature available to avoid accidentally turning on the light while packed away: holding down both buttons at the same time.One thing I’m a bit concerned about is is the tab that holds the battery cover in place. I’m a bit worried about material fatigue of these tabs and about changing batteries in very cold conditions, when plastic tends to get brittle. Another concern is the IPX8 rating. Technically, I should not have to worry about the Cosmo 350 falling in the water as long as it’s fished out quickly. Looking closely at the light, the battery compartment does not look like it’s IPX8. That may be OK in freshwater, but definitely not in saltwater.Yes, there are much more powerful headlamps available, and I do have a couple. But I'd say that the Cosmo 350 covers at least 90% of my night time activities, which include night orienteering, hiking, camping, fishing and astophotography. All in all, the Black Diamond Cosmo 350 is a great lightweight headlamp putting a lot of features and a respectable battery life in a small and inexpensive package. In spite of the concerns I noted, I am giving five stars because of the low price of the headlamp.

Three batteries offers a reasonable burn time & weight balance. At this price point there is virtually no reason for failing to carry a light in the backcountry. 350 lumens is more than adequate unless your planning on speed skiing at night on cluttered terrain. The increasing lumen contest Is dangerous - oncoming headlights from cars, bikes, pedestrians are completely blinding. If your using this in the cold, then get disposable lithium ion batteries or the rechargeable pack. Alkaline batteries perform poorly in the winter because they have water-based electrolyte & can burst when frozen. Li-ion batteries will also have a shorter run time, but they won't burst.