Black Diamond Cosmo Headlamp

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Black Diamond Cosmo Headlamp Review Facts

The Black Diamond Cosmo Headlamp is ideal for any outdoor activity, sport, or task, such as backpacking, camping, and running. It has just one button to operate the modes and adjustments you want to make to the light beam for an easier operation. The six settings include night vision in red, lock mode, dimming, strobe, and distance and proximity modes.

To turn it on or off, you just simply hold down the button. It is not like some other models that have to go through the various cycles to go off. The Cosmo operates on AAA batteries that are included with the purchase, and it has ninety lumens of light. The greatest beam distance is seventy meters with the light fading at the edges for a more natural view.

This Black Diamond product is comfortable and waterproof in many types of environments. It is perfect for weathering storms because of its resistance to water. it can even be submerged safely up to a certain depth and length of time. There are a few concerns from buyers about the Cosmo, but nothing that would deter the serious buyer from investing in this sound piece of gear for their backpack.

We discuss the features and qualities of this high-quality headlamp below in greater detail. If interested in other models of Black Diamond you can check also their Spot Headlamp.

Editor's Pros & Cons
  • Shuts off and turns on with the press of the button
  • Light fades at the edges of the light beam
  • All modes can be operated with one button
  • Best beam distance is 70 meters
  • Good for running, camping, or backpacking and others
  • Use for camping bathroom trips at night
  • Is waterproof and stormproof
  • Some people do not like just one button for the control of the modes
  • Button can be too easy to push - can come on in a pack by itself


The Cosmo from Black Diamond comes in a choice of four colors that can match your outdoor gear, such as duffels or backpacks. It is one of the most comfortable headlights on the market because of its light weight and ease of use. because it has just one button, you will not have to worry about trying to find the right button to change the mode, adjust the light, or turn it on and off. Some people found the one button problematic, but the majority of buyers liked it. You do not have to cycle through the various modes to shut it off either like you have to with some other models of headlamps. Just hold the button down to turn it out or on and that is it. The light beam fades at the edges nicely to not show a circle of light in front of you. This fade is important to those who do not want to look through a solid cone of light. The comfort level of the Cosmo is great.


You do have some flexibility with this Black Diamond product. All modes can be controlled with just the one button, plus there is a good seventy-degree tilt to the light when it is worn. You can move your head around a fairly good range to see things to work on or to see things on the side of you when running and jogging on a trail. This range of motion would be best appreciated by those that run or job in the early morning or the evening because they can see things in the dark quickly with just the tilt of their head. Many buyers said they purchased this light for these activities, so they would not have to hold a light in their hands. The settings include lock mode, night vision in red, strobe, dimming, distance and proximity modes. These can be used in varying light adjustments as you need them. Because the Cosmo only weighs 2.88 ounces, it can be part of your activity, work, and sports gear all the time. The flexibility of this item is high.

Key Features

-Do not have to cycle through modes to shut it off
-Light fades at the edges of the beam
-Includes six mode settings for day and night vision
-All modes can be operated with one button
-Has an almost 70-degree tilt and ninety lumens
-Best beam distance is 70 meters
-Change modes and adjust the brightness easily
-Has one double-powered and one triple-powered LED light
-Is waterproof for thirty minutes at 3.3 feet or one meter
-Great for weathering through storms
-Comes with batteries for operation


The best beam distance of the Black Diamond Cosmo is seventy meters and on low, it is ten meters. Although this is not the farthest distance of headlamps in general, it is one of the greater distances, when all popular models are considered. This terrific product runs on AAA batteries for operation, and the average run is 180 hours on low and 30 hours on high. Some customers used just two sets of batteries every day over a whole summer with high usage. You can save on the battery life by adjusting the lighting and the modes when you do not need such a strong light. (We mention more about powering this light in the section on the power source.) one buyer mentioned that the battery compartment is not protected from water, and this is true. The manufacturer comments about this issue by stating that if the battery area is submerged, it will still function. You should dry it out as soon as possible after this happens for the best, continued operation.


The many modes of the Cosmo offer you stability in choosing one of them and then keeping it in that mode as long as you want. When you turn the lamp off in a certain mode and brightness, you will not have to cycle through the other modes to get back to it when you turn the light back on. This has been a common problem with other current models and has aggravated users with the continued searching for the mode and brightness they want. Also, another stable feature of this Black Diamond model is that the night vision activates without having to go through the other mode of white. It remembers your settings and keeps them until you change them yourself. Changing the modes and adjusting the brightness is easy and simple with the one button on this lamp.
This is a staple item that you can depend on.


The design of the Cosmo is low-profile and sleek. It has one double-powered LED white emit lumen light and one triple-powered LED light. You get strobe and dimming modes with the night vision with this item. One consumer who purchased the Cosmo noticed that the white beam light has a yellow center that can bother some people. The company acknowledged the complaint and said that it was intended to help the user focus better. It is a spot that follows the user around, which could be annoying. For example, if you look at your arm with the white light on it, you would see a spot that looked like a bruise. No one else commented about this yellow center, but we think it is worth mentioning in our review of this product. The style of the Cosmo is an all-around headlamp that can be used for many purposes and many different environments.


Being a high-quality lamp, the Cosmo is very supportive of your lighting needs. Because this model only has the one button for all its operations of selecting the modes and the adjustments, some people did not prefer this. They thought it cumbersome to deal with just the one button. Others found that the button can be easily pressed by objects in a backpack or duffel. By the time you find this out, possible during camping or backpacking, the batteries would be expired. One person found that after an extended period of time, the band to hold the light on the head stretches out of shape, making it hard to keep on the head. A runner also stated that while running the light flickers often and sometimes does not light the far distance enough for them to be comfortable with. These are isolated comments but do need to be considered when you are shopping for the best headlamp for your individual needs. It is important to note that Black Diamond is very serious about their warranty, even years later after the purchase. One person had to return theirs after two years, and the company did the exchange hassle-free and free of all shipping charges.


Ideal for jogging and running in the morning or at night, the Cosmo is best used for backpacking. This is because this activity requires hands-free operation at times when light may not be available. it is good also for camping or any other task, sport, or activity you need a source of light for. When camping, it is important to light the way for bathroom trips at night. many people keep this light in their backpacks or vehicles just to be ready for any emergency or event where such a light would be needed.


This amazing Black Diamond item works through storms, splashes, and sprinkles of water. the housing was redesigned on this version to make it waterproof, as far as the electronics of the lamp. It is protected from water for thirty minutes at 3.3 feet or one meter, id it becomes submerged. If this does happen, and it is submerged, the battery area needs to be dried out when you get to shelter. This is one of the best lamps being sold currently for being waterproof.

Power Source

For the power of the Cosmo, it needs AAA batteries. The lamp comes with a set of batteries to get you started right away but will require a backup set when they expire. It has ninety lumens of light in a strong beam that will shine quite a long distance. Please note, as was stated previously, that the battery compartment is not sealed to make this 100% waterproof. This is important to know because it must be dried when it does get wet.

The Bottom Line

Despite the few minor complaints about the Black Diamond Cosmo Headlamp, we think it is an excellent product. It is a redesigned model from previous lamps that focuses on the one-button operation and the waterproof body. Multiple buttons can be a problem to navigate when you are participating in your activity in the dark. The fumbling around or trying to remember which button was for what issue is over. Just the one button will take you through the different modes and the light adjustments, so you can find the exact type you need. This flexibility and ease of operation are perfect for activities like camping and backpacking, where such a lamp is needed to free the busy hands at work. Many times, duties and tasks must be completed in the early morning or late-night hours and such a lamp is required. For runners and joggers, it is a safety mechanism for others to see them from a distance in the dark. Being waterproof just adds to the versatility and freedom in using this headlamp. It is waterproof for up to thirty minutes submerged in water or for 3.3 feet. This feature makes it perfect for storm preparation tasks and for those that work in wet environments. It is a comfortable light to wear on the head for long periods of time and allows a good range of tilt and motion when your focus area changes. The few negative comments about the band stretching over time, the yellow center to the white light, and the single button for all controls are minor complaints when you consider all that this light can do for you. The button can probably be easily pressed in a backpack or duffel by other objects because there is nothing to protect it, but with careful planning in packing, this can be avoided easily. Overall, the Black Diamond Cosmo is an outstanding headlamp worth purchasing and owning for when you need to see in the dark with your hands free.