Arcteryx FL 45 Rucsac Review

Rich testing the FL45 on the crux of the Croz Spur, Grande Jorrasses North Face
Rich putting the FL45 through it’s paces on the crux of the Croz Spur, Grande Jorrasses North Face

We’ve been using the FL 45 this summer (if you can call it that!) in the alps and it’s proved to be a perfect alpine summer pack so far.  The weight is impressive for a pack of this size at only 650gms, but this hasn’t been achieved through the use of a flimsy fabric; rather through intelligent, minimalist design.  The fabric feels very burly and durable and thanks to the sealed seams is completely waterproof, doing away with the need for liners etc and saving extra weight.  This would make it a good winter sack for Scotland and icefall cragging etc and we’re looking forward to testing it in these conditions over the winter.  I guess it would also make it a good minimalist backpacking sack for wet weather conditions – there can’t be many lighter, more waterproof sacks on the market at the moment.

Over the past summer the bag has been used for alpine rock routes, classical mountaineering and ice and mixed climbing (both off lifts and with overnights in huts) and also for a couple of alpine north faces with bivouacs (carrying light sleeping bag/bivvy bag, jetboil and 2/3 days food).  With this in mind, this is what we’ve found out about it to date:


lightly padded shoulder straps
lightly padded shoulder straps

The shoulder straps are slim, with soft fabric edges and relatively light padding, whilst the waist belt is a simple webbing strap with quick release buckle that can be centered.  Despite the simple design it’s just comfortable enough even when the bag is fully loaded with climbing and bivvy kit and very comfy for standard day use, even wearing thin layers.  Attachment points seem very robust and there’s a handy loop where the shoulder and waist straps meet, which is good for clipping axes to when rappeling etc.  It keeps them out of the way of your abseil rig and your harness so you can access your rack/abolokov threader etc, but handy enough for quick access. Inside the sack there is a thin foam pad which is laminated onto the back, forming a simple back system – just enough to stop your rack digging in your ribs, but still flexible and light.  To finish off, there are 2 bar tacked haul loops – one in the conventional place as a grab handle and another small one on the front of the sack, creating a simple balanced system.  In use, the sack sits quite high, which gives good access to your harness and doesn’t catch too much when descending scrambly terrain facing out – great for guiding situations.


extension tube pushed inside
extension tube pushed inside

With the main body of the sack fully loaded, the bag comes in at 32L – which is great for day routes on alpine terrain and most things can be stashed inside at this size, with just axes going on the outside.  With the inner drybag style extension the bag becomes a 45L and although it looks a bit strange, it’s a logical way to extend the size for an approach walk – ie when carrying extra layers or water proofs etc – but then the bag becomes a sleek climbing machine once the extension isn’t required – so a great way to optimize load size and the way the bag climbs.  In day to day use, the extension isn’t really needed and I found the best thing was to push it down inside the sack, using just the main draw cord for quick access.  Even in light rain, if the sack is packed well, the draw cord does a good enough job of keeping things dry inside. When the drybag is pushed inside the main compartment like this, it’s light grey colour makes things easy to see in the depths of the sack – a nice touch and typical of Arcteryx’ attention to detail.


There is a simple small flat pocket on the front/top of the sack. When fully loaded, it’s tricky to access and is then only good for small items like topos and keys etc.  When partially loaded, it expands a bit better and you could fit a few munchy bars, sunglasses etc in there – but it’s definitely not a conventional ‘top pocket’.  With this in mind, it’s best to use a small stuff sack for most of your small items and stash this under your helmet at the top of the main compartment.  It takes a bit of getting used to, but the main drawstring is really well designed for one handed opening, so it’s actually quite quick to access.

Attachment Points

bungy external attachment system
bungy external attachment system

The bungy system for attaching gear to the outside of the pack takes a bit of getting used to, but works well and is super flexible for carrying all your tech kit on the walk in.  You’ll need some extra cord to attach a sleeping mat to the side (there are spare tabs of sturdy webbing to do this), but once climbing the mat sits best on the front of the sack out of the way and a full length karrimat just fits under the bungy. The system is very light and simple and the axe keepers (alloy bars which push through the hole in the head of your axe) work well, although a bit fiddly with gloves on.  The bungy is quite thin, but seems to be wearing well and it would be very simple to replace anyway.  The top strap is quite long and holds a rope securely on top of the sack if required, even when the extension tube  is fully loaded. There’s a nifty little Velcro tab that secures the excess and stops it flapping, but I found this annoying and eventually just tied a loop in the end to shorten it.  Al managed to break the buckle on this top strap by picking the sac up by it whilst fully loaded and stepping out of a cable car, so a bit of care is required with it.


Some people will miss the inclusion of a simple water carrier sleeve against the back pad, which can also be useful for guidebooks etc and wouldn’t add much to the weight.  It can feel a bit clumsy if you need to remove a rope and platypus to get access to your stuff sack for sun cream etc.  A small gripe though and once you embrace the lightness and simplicity of it over a conventional sack, this seems a small compromise.


We’re really impressed with this piece of kit – it’s been a joy to use so far and we’re looking forward to abusing it further over the winter!