To fully enjoy caving exploration, the main piece of equipment, in my opinion, is a high-quality source of light. In our circle of colleagues cavers, we often debate which is the best caving headlamp. We all agree that French company Petz produce exceptionally high quality outdoor and extreme sports gear, also when it comes to caving and headlamps.

The most crucial factor when choosing the right caving headlamp is safety! When you are 1000 feet underground the lamp MUST be damn reliable. Your life pretty much depends on it.

This is why we cavers believe that Petz DUO S does a great job. It is robust, has a high light output, good lifespan, etc.

When visiting caves the rule number one is that you need AT LEAST two separate sources of light. Of which the second (spare) must be as reliable as the main one. For my spare, I use just another DUO S. I prefer my life much more over a coin! 😉 At the end of the article, I mention what other models my friends cavers also use for spare lights.


Why We Are Sure Petzl DUO S is the Best Caving Headlamp

Petzl DUO S - Best Caving Headlamp

The lightning performance is amazing. In boost mode, t has a max of 1100 lumen. There are 6 different lighting modes each with different beam patterns, brightness, lightning distances and battery burn time (see the table below). It is fully dust, mud and waterproof, perfect for conditions inside the caves. Very robust, resistant to falls and big impacts. It comes with a rechargeable 3200 mAh Lithium-Ion battery (spares can be bought separately), which you can fully charge in 4 hours.

Another interesting feature is the “Face2Face” function. The lamp has a light sensor and when the two beams cross each other the lamp dims the light automatically. This enables DUO headlamp users to face each other without blinding one another.

The lamp is operated with a big easy-to-use button, even with gloves can be handled with ease. It can be attached to any type of caving helmet due to “PRO ADAPT” adhesive plates. For accessories scroll a bit further down the page.



  • Weight: 370 g
  • Beam pattern: wide, mixed or focused
  • Energy: 3200 mAh Lithium-Ion “ACCU 2” battery (included, also can be bought as spare ones)
  • Recharge time: 4 h
  • Watertightness: IP 67 (waterproof to -1 meter for 30 minutes in fresh water)

Petzl DUO S comes with “ACCU 2” Lithium-Ion rechargeable battery (3200 mAh) and 110/240 V charger.


Lightning Performance

Lighting ModesBeam PatternBrightnessDistanceBurn TimeReserve Mode
close-range work


80 lm

20 m

23 h



180 lm

35 m




330 lm

70 m

6 h

20 lm for 45 min

rapid movement


700 lm

160 m


distance vision


450 lm

190 m


BOOST mode


1100 lm

200 m


Pros & Cons


  1100 Max Lumens

   At 1100 lumen not more than 1 hour of use.

   Good materials, robust, resistant to falls and big impacts

   No custom mode settings



   Multiple beam types




Petzl Vertex Vent


Although this is not the latest Petzl Caving helmet, I prefer it over others. It just fits my head perfectly. Some other friends cavers also have the latest Petzl Boreo. Also very comfortable and robust. If choosing Boreo, keep in mind there are two sizes: S/M (48-58 cm) and M/L (53-61 cm).

Petzl PRO ADAPT (Duo Mount)


You will need these two adhesive plates to mount the lamp (and battery on the back) to your helmet. It fits any helmet's surface curvature.


Spare Lights

Here’s a list of spare lights we use while going caving. As I said before, I use another Petzl DUO S.

But for some, a spare light is best worn around your neck in a case of a hurry. Let’s say your main light fails in the middle of ascending/descending a high vertical. That’s why the one with an elasticated strap is the most suitable. And once again, it MUST be as reliable as the main one!


Zebralight H502 L2 AA


Tough and firm headlight. Very versatile as it has 6 modes. Ranging from the highest: 278 lumens,  54 mins runtime, to the lowest:  0.06 lumens, 2 months runtime.

It is powered by 1 x AA (alkaline, NiMH or lithium) battery.


I wish you an enjoyabe and safe caving exploration.