Black Diamond Cosmo 350 Headlamp
- 350 lumens, dimmable
- 3 AAA batteries included, or BD 1500 Li-ion
- IP67, 1 meter for 30 minutes
- Strobe and red night vision modes
- 3 year warranty
- 4 x 3 x 2 inches, polycarbonate
Last refreshed Sep 10, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A light, dual fuel headlamp for hiking and camp chores that runs on AAA cells or an optional rechargeable. Runtime and beam distance are not listed.
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ASIN: B0H1X5J79NModel: Cosmo 350Category: Headlamps
Colors Available
Sizes Available
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Overview
Not a rechargeable-only lamp, the Black Diamond Cosmo runs on ordinary AAA cells or the brand's optional lithium pack. A single button handles dimming, strobe and red night vision, and a low-profile body rides on an adjustable headband.
Dual fuel power means spare AAA cells from any store will keep it running on a long trip. The listing gives no runtime or beam distance, so planning battery spares is guesswork.
Who it's for
Campers, hikers and home emergency kits get a simple lamp with easy battery swaps. Night athletes who plan around exact burn times should choose a lamp with full runtime data.
Pros and cons
- Runs on AAA or rechargeable pack
- Survives brief submersion
- Red mode for night vision
- Low-profile, light design
- Runtime not listed
- Rechargeable pack sold separately
- Must be dried after wet use
Performance notes
Brightness and burn time depend on the battery in use and the dimming level chosen. Alkaline AAA cells fade gradually, while the rechargeable pack is the brand's alternative. The waterproof seal handles rain and a dunk, but the lamp should be dried out after wet use.
Specifications
| Brand | BLACK DIAMOND |
|---|---|
| Model | Cosmo 350 |
| Dimensions & fit | |
| Item Dimensions L x W x H | 4 x 3 x 2 inches |
| Capacity & performance | |
| Light Output Maximum | 350 lumens |
| Power & efficiency | |
| Battery Description | 3 AAA (included) |
| Battery compatibility | BD 1500 Li-ion rechargeable |
| Construction & materials | |
| Material Type | Polycarbonate |
| Color | BD Graphite |
| Compatibility & installation | |
| Mounting Type | Head mount, adjustable headband |
| Warranty & support | |
| Manufacturer Warranty Description | 3 year warranty |
| Other details | |
| Water Resistance Level | IP67, 1 meter for 30 minutes |
| Light Source Type | LED |
| Light Source Special Features | Strobe, red night vision |
| Additional Features | Dimmable |
Frequently asked questions
Can the Black Diamond Cosmo 350 be recharged?
Only with the separate BD 1500 Li-ion battery; it also runs on standard AAA cells.
Can the Black Diamond Cosmo 350 get wet?
Yes. It is IP67 waterproof and works after submersion up to 1 meter for 30 minutes; dry it fully afterward.
Does the Black Diamond Cosmo 350 have a red light?
Yes, plus strobe and dimming modes.