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CustomDUO modules

CustomDUO LED Modules offer a significant upgrade for the Petzl Duo, replacing standard halogen bulbs and Petzl 5-14 LED clusters. CustomDUO modules are super reliable, and are very easy to fit in any original (pre 2018) Duo. 


The original Petzl Duo was produced from the late 1990s, principally as a helmet mounted caving lamp, before high power LEDs were widely available. The original Duo is without doubt the most widely used caving lamp. Other than the lack of light output and run time from the original bulbs, the Duo has proven extremely fit for purpose, with a comfortable 5m depth rating (will handle deeper !!). The Duo is suitably robust, typically withstanding a good few years of gnarly caving. It is easy to operate, having a caver friendly switch, is light weight and seats very well when helmet mounted. The battery box is easily opened, and is practical, using low cost, widely available AA batteries, which can withstand significant mistreatment when carrying spares. 


Since 2009, CustomDUO have developed a flexible range of LED modules to meet individual needs, including the best selling Omni modules (Omni v5 and Omni 'Simple'). CustomDUO modules are without doubt the brightest, and most effective retrofit LED upgrades available for the Duo, featuring practical power settings and user friendly operation, developed specifically for cavers. CustomDUO modules use the latest high power LEDs, significantly increasing light output and run time. Plenty of both for even the most pushing of caving trips. Incidentally, the very first LED conversions for the Petzl Duo were constructed by innovative French cavers (not Petzl). These conversions incorporated a number of Nichia LEDs (5 - 8 from memory), and looked very similar to the Petzl modu'led 5 which they pre-dated. They were available from Expe in the Vercor as early as summer 2000, at least that is when we first recall seeing them.  


With a CustomDUO LED upgrade, (and decent quality low self discharge NiMh AA batteries), the original pre 2018 Petzl Duo has established itself as the outstanding low-mid cost helmet mounted caving lamp. A great choice for novices and serious expedition cavers alike. 


Petzl Duo LED upgrades 

Availability of original (pre 2018) Duo - upgradeable 

The original pre 2018 Duo is now discontinued. However, new stock is widely available and can still be purchased through specialist caving equipment retailers, and on line sources.  Due to it's upgradeable design and suitability for caving, astute retailers bagged surplus stock from Petzl, prior to launch of the industrial workplace orientated Duo models (Duo Z and Duo S). CustomDUO LED upgrade modules work with all original pre 2018 Petzl Duos (see fitting information).


An original Petzl Duo 5 LED version with headband, which can be easily modified to helmet fixing 'fixo' specification, will cost approx. £65 uk new (Sept 2018). The 5 LED version is the lowest cost format. A 14 LED head band or helmet fixing version will cost a little more. The only difference is the lamp internals (LED cluster and reflector) and this is obviously an unnecessary expense when upgrading with a CustomDUO LED module. From a caving perspective, we would generally advise sticking to the 4xAA battery models (avoiding the accu pack and Duo belt versions).


It is also likely that there will be a steady ongoing supply of good condition used Duos, the most obvious source being Ebay. A large number of original Duos were manufactured and sold over the last 20 years. Many were sold for low impact leisure activities such as hill walking. This market has now been largely replaced by bright, low cost head lamps that do not need to offer the robustness and other qualities essential from a caving lamp. Good used condition Duos will no doubt be available for a long time. 


We wouldn't advocate that you panic just yet, but we do understand that some cavers have already stockpiled one or more original Petzl Duos. It's hard to argue with this logic, when an original Duo with CustomDUO LED upgrade outperforms the new DUO z2 on every measure important to the well considered caver. 



Guide to converting an original headband Duo to helmet fixing 'fixo' specification


CustomDUO LED modules are not compatible with new Petzl Duo Z (and Duo S) models, released early 2018. These new Duo models are a fully sealed design and are not upgradeable, and while they can be helmet mounted, we understand that this is limited to the Petzl Vertex and Alveo, not exactly the cavers preference. 


The new Duos are aimed principally at the high volume industrial workplace market, probably with half an eye on commercial outdoor activity providers. There is a 4xAA version and also li-ion battery pack based models. With slick marketing, these will no doubt sell in good numbers to their principle target audience. However, from a cavers perspective, it would be very difficult to make any positive argument for the new z2 Duo, versus the original pre 2018 4xAA Duo.  But the gear shops can only push what is currently available, and the new Duo is already being discounted !!


The original Duo can be upgraded with LED modules that feature the very latest, most efficient LEDs. CustomDUO modules currently provide approaching 200 lumens per watt, far beyond the performance level of mass market lights using unspecified LEDs. The LEDs used in the new Duo z2 are not specified. However, tech info states that it has 4 mixed flood and spot LED light settings from 50 lumens (15 hours) to 220 lumens (2 hours), plus a 430 lumen short burst feature. This performance information is sketchy at best, but suggests (as you might expect) that light efficiency, output and run times are well below what is readily achieved with a CustomDUO LED upgrade, original Duo and some good quality nimh AAs.


The superior performance and upgradeability of the original Duo aside, the advantages continue. From a cavers perspective, it is robust, light weight, easy to operate and significantly cheaper than the new models. It is simple to swap batteries, and is easily and securely helmet mounted. It is immediately compatible with most helmets, including models typically preferred by cavers. Importantly, from a caving perspective, the original Duo is also depth rated to -5m, and can withstand a little bit more than that. 


We could go on, but you probably get the idea. Things just don't always get better.




New Duo Z2 (from 2018) - not upgradeable

gallery/petzl fixo
gallery/petzl duo z2
gallery/z2 lamp
gallery/z2 box

  Duo Omni

  Omni 'Simple'

  Gecko Spot

  Gecko Side

Original upgradeable Petzl Duo (pre 2018)

Petzl Duo z2 (from 2018) Not upgradeable

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