Rab Photon Pants review

By Matthew Dieumegard-Thornton

The Rab Photon Pants are a 100g Primaloft pant, which perfectly span the gap between full-weight expedition down pants/suits and the Mountain Equipment Stretch Pants or similar models.

Due to their Primaloft insulation, they are also extremely versatile, with the ability to be used in fickle conditions such as extreme-cold belays and snow holes in Scotland. They are, however, for the most part, too warm for the UK climate and are much more suited to high-altitude mountaineering.

Rab Photon Pants

Rab Photon Pants

Their forte is altitudes of about 7,000m, where although a down pant may be worn, they are certainly not necessary. An example of this is for an expedition to climb Everest’s North Col. This expedition goes no further than the 7,020m col, and so a down pant is not needed. Instead, the Rab Photon Pants are a perfect alternative.

Similarly, I used them on my Baruntse expedition in 2011. For the preparatory summit of Mera Peak, they were not needed, instead summiting in Mountain Equipment Stretch Pants. For Baruntse, however, the Photon Pants were perfect, keeping me warm all the way up to the 7,129m summit.

On the descent, I wore these pants down to base camp at about 5,000m for two reasons. Firstly, I was utterly exhausted and just climbing down was a Herculean task, so changing trousers was certainly out of the question. Secondly, the only reason I was able to keep the Rab Photon Pants on for so long was their full-length zips, which are one of the best features of the pants, second only to their warmth.

Their warmth is incredible. On picking them up, they are exceptionally lightweight, at 450g, but their weight definitely belies their warmth. For a photo shoot prior to climbing Peak Lenin, I wore the Rab Photo Pants for only ten minutes, at which point I took them off to find my legs dripping with sweat.

The zips are not only full length, but also allow the pants to be put on without removing boots or crampons, as they completely unzip on both legs. These zips are also invaluable on warm descents or later in the day on the ascent when venting is needed. The nature of the zips means the ventilation can be completely tailored to you immediate needs.


The main strengths of the Rab Photon Pants are their warmth and weight. They also perfectly fill the gap for 7,000m peaks and have great features, such as full-length zips, plus two zipped pockets and two hand-warmer pockets.


Their waist sizing is on the large side, but this is easily remedied by a belt.


An exceptionally warm pant that perfectly covers the transition between warm soft-shell pants and down pants/suits, and with endless uses. The Rab Photon Pants’ potential uses are: winter climbing, mountaineering, winter walking, backpacking, bivvying, mountain marathons, military, angling, base camping, expeditions and spectator sports.

Rating: 5/5

Follow Matthew on Twitter @MattDThornton or visit his website, http://www.matthewdthornton.com/Home.html

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