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The Fastpack 35 is now my favourite backpack. I’ve used it extensively in the last 2 years for every multi day adventure I’ve had. The combination of extreme lightness, waterproof roll up dry bag entry, front pockets and pouches for snacks and water bottles and that you can adjust it bigger or smaller means it can carry everything up to a lightweight tent, sleeping bag and overnight gear and still feel secure and light enough to trail run wearing.

Ultimate Direction Fastpack 35

In Depth Review

 I first tested this bag 2 years ago on a  Fastest Known Time  record attempt on the Sussex Border Path but I’ve gone on to use it for my Leatherman Loop, New England Trail records in the USA as well as both through hikes of the CT section of the Appalachian Trail.

What is a Fastpack?

So what is a Fastpack ? Fastpacking is the natural outcome from slower long distance runners like me who do lots of self supported multi day running with outdoor camping.  I tend to see myself as much as a fast hiker as I am a slow ultra runner.  For multi day running with no checkpoints or crews you need to carry a few extra items with you like sleeping bag , small tent or bivvy bag , extra waterproof gear and charging packs for power so the standard 14L or small race vest simply isn’t big enough.  Ultimate Direction have dominated this ‘Fastpacker’ niche with the industry standard for years in the form of the Fastpack 25 .  

The Ultimate Direction Size Choice 15L, 25L or 35L ?

The Ultimate Direction Fastpack Range is rather varied. The 25L Fastpack  is superb and I’ve used one for a few years but the 15L Fastpack is awful ( it has a non waterproof zip right up the middle of the whole bag so everything gets wet if it rains and it is just the wrong size for everything, too big for single day too small for multi day).  There is also now a female FastpackHER which I have reviewed and wasn’t impressed with.

Lee-Stuart Evans Setting the fastest known time on the 141 mile Sussex Border Path using an Ultimate Direction Fastpack 35

Side by Side with the Fastpack 25

When I initially got the bag I couldn’t understand why it looked exactly the same as my Fastpack 25. This made no sense. How have they added 10 more litres of storage? It wasn’t until I looked at the depth of the bag that I realised that was where the extra room come from. This has a very interesting side effect, the bag feels no more bulky on your body than the fastpack 25 but it means the side bungee storage mesh pockets and much wider and longer so its much much easier to reach back with your hands while wearing it to take things in and out.

At first glance the Ultimate Direction Fastpack 35 ( left) and 25 (right) look the same size !

Fabric

The material feels a little bit more hard wearing than the older Fastpack 25 I had and with hardly any weight difference its easy to see why you would opt for a 35L bag over its smaller brother because  you can easily roll it down and make it smaller than a 25L bag but with a 25L you cant make it any bigger.

The UD 750ml bottles sit a bit high in the pouch for my liking on the Ultimate Direction Fastpack 35

Water Bottle Pouches and Chest Pockets

The water bottle and pockets configuration on the Fastpack 35L is an improvement too. I like the high zip pocket on the left breast as its big enough to fit my smartphone and a charger pack so I can charge phone or watch or torch on the move easily. It has numerous extra stretchy pounches for gels and snacks ( far more than the Fastpack 25) but you lose the ability to have 2 water bottles up front with the high zip pocket. The old Fastpack 25L used to be able to handle 2 x 750ml hard bottles easily but for some reason the Fastpack 35L leaves the water bottle a bit too high and near my neck and face with a 750ml bottle so I opted to use 600ml softflasks instead which works great, one up front and one stowed in a side or rear pouch.

plenty of room for gels and snacks in the multitude of zip pockets and stretchy pouches on the Ultimate Direction Fastpack 35

Gripes

The new range of UD race vests have an upgraded and thicker and more hard wearing bungee to mount your poles near the bottles so its shame to see that the Fastpack 35 hasn’t adopted this and still has the flimsier bungee. After a lot of use they fray and eventually split off. While I’m having a little moan the new chest clips are fiddly, the old standard clips on the fastpack 25 I had worked either way up, the new ones have to be the right way round. When you are tired or it night this is infuriating. I cant see any advantage to these new clips, only downsides.

I hate the new fiddly clips on the Ultimate Direction Fastpack 35

Adjustable and Secure Even When Running

Removable Sponge Back

Adjustable to Lots of Different Body Shapes

You can now adjust the height of the chest straps AND the side strap height so you can customise even more for your body shape. This is good progress from the UD FP 25 but I’d still like to see a female version of this pack and not a ‘unisex’ set up.  They do a Jenny Race vest for women so its about time UD do a female Fastpack ( update – I hear from UD there IS a female FastpackHer coming out soon !).

5 different height options on loops for the side straps of the Ultimate Direction Fastpack 35

Waterproof and Breathable

Seamless Comfort – No Chaffing

The Fastpacks are made from a unique seamless infinity desgn which means there are no seams on any of the sections that contact your body. This makes this immensely comfortable and in fact when I was hot ( it was a baking hot 27 that weekend)  I ran significant sections with no t shirt on at all in total comfort (apologies to the odd walker that saw me. I was too hot to care)

Enough Storage for All Your Overnight Gear

My 35 L bag had more than enough room in for a sleeping bag,  inflatable roll mat, spare clothes, waterproof jacket and trousers, spare socks, charging pack and gear and bivvy bag with loads of room to spare. With the 25L I would be close to capacity on the bag for multi day adventures which can make rummaging round in the bag a pain. the 35L is much better but comes with a word of warning …. you need to be disciplined with your packing or you WILL fill that extra 10L with stuff you don’t really need. I slept ‘rough’ a few times during the weekend in 2 to 3 hour stints. The extra space meant I could bring a few extra ‘luxuries’ like an inflatable roll mat without having to mount anything on the outside like I normally do with the Fastpack 25.

The huge and very stretchy main outer mesh pouch across the back of the Ultimate Direction Fastpack 35

A Huge Stretchy Mesh Pocket for Easy Stowage of High Use Items

The rear massive bungee mesh area remains a feature shared with the FP 25  and I love it. I tend to fill it with stuff I need quickly like a waterpoof jacket or headtorch that can stand being rained on .

Storing a drybag beneath the Ultimate Direction Fastpack 35 is easy when I go wild swimming

Daisy Chain Attachments Loops for Extra Gear

There are huge numbers of places to mount small karabiners or bungee to attach clothing or gear  to on the outside, it has loops for ice axes and various ‘daisy chain’ loops and 2 of its own bungees to accommodate any extra gear you want to stow on the outside easily .

The waterproof zip pouch at the rear of the Ultimate Direction Fastpack 35 for things like keys and wallet.

Waterproof Outer Zip Pocket

Easy to Wash and Reproof

All in all there is very little difference in price between the fastpack 25 and the Fastpack 35 and I would say the 35 is worth the extra money. You can always make a bigger bag smaller ….but you cant make a smaller bag bigger. You could even finally see a Marathon des Sables runner using this bag and be one of very few to have everything inside the bag on day one !

Sussex Border Path

I finished the 141 mile Sussex Border Path  in 3 days and set a new record.  An average of 50 miles per day in hot conditions and 10,000 ft of ascent. the right pack with the right amount of comfort and features is really important when you are quite literally living out of your bag for 3 days and nights.  This was fastpacking at its absolute best and I loved almost all of it.

Fastpacking means seeing sunrises like this on the Sussex Border Path

Verdict 

Verdict