ABOUT THE THULE RAIL 4L HIP PACK
The Rail 4L is the largest Hip Pack in Thule’s wide lineup of mountain bike packs. Offering 4L storage capacity which includes a 1.5L hydration bladder, Thule suggests the Rail 4L to be a perfect pack to tackle rides up to three hours in length.
The Rail 4L Hip Pack is manufactured to Bluesign® standards for environmental and working standards. Using a mix of synthetic materials, Thule designed the pack to be durable but offer comfort and breathability where required. A generous padded mesh material is used against the back to offer stability and reduce heat buildup against your back. A stretch mesh waistband with hook and loop fastening helps to keep things in check, further secured by a strap with buckle and dual side adjustment.
The included 1.5L hydration bladder sits within a sleeve inside the main pocket. It uses a roll and slide-top design to offer a wide opening for refilling with good security against leakage. Securing the hose when not in use is the genius ReTrakt magnet system, which easily snaps in place to securely stow the hose without fuss.
Inside the main zipper pocket of this 4-liter hip pack is a variety of pockets and dividers to keep items secure. There’s a padded side-entry pocket designed for a phone, then an outer pocket with hook-and-loop flap for quick access. On each flank is a stretch mesh pocket for the easiest snack access.
The Thule Rail Hip Packs are offered in 0L (0.5L actual capacity); 2L or 4L variants, in the Khaki color only. The 4L version tested retails for $109.95 / £94.99 / €109.95.
THE DIRT
Once loaded up with all my ride essentials: tools including a OneUp EDC tire pump and Lezyne Digital Shock Drive; plentiful snacks for my ride (plus extras just-in-case); a Rab Cinder Phantom rain jacket, and the full hydration bladder, every single mL of that 4L capacity was used.
Testing the Thule Rail 4L Hip Pack on the tight and twisty rowdiness that forms my local trails was always going to push it to its limits, and it came very close to passing the test, but ultimately struggled to remain stable in the most dynamic of trail scenarios. I found it could be tricky to secure the pack properly when fully loaded, too, as the hook-and-loop of the first strap was not strong enough to hold the pack until the buckle was secured. Not impossible by any means, but I have a knack of making all but the simplest of tasks difficult at times.
Dialling back the loadout to include no extra layer and only 1L of fluid, and this Thule hip pack immediately came into its own. With the straps cinched tight, it remained stable and comfortable throughout the duration of the rides. The organisation options are all well considered, with the side-entry phone access impressively easy to find and use with one hand.
The ReTrakt hydration hose storage is simply genius. So simple yet so effective, this long strip magnet lets you simply wave the hose in the general vicinity of the waist strap, and not once did it fail to latch on. Impressively it also didn’t come loose in use throughout testing, sticking firmly in place until hydration was desired.
After extensive testing across the spectrum of conditions, I’ve found myself happy using the Thule Rail 4L hip pack for the majority of my rides, and it continues to perform every bit as good as day one. After a couple of spills and plenty of time being attacked by dirt fired off my back wheel it’s still holding up, with no signs of it giving up any time soon. I’d love to see a more subdued black or grey color option, but the Khaki makes for a nice looking pack all the same.
The Wolf’s Last Word
Provided you don’t load the Thule Rail 4L Hip Pack to the absolute maximum of its capacity, it offers a secure and comfortable pack with some neat features. With this in mind, if you consider it to have a 3L capacity then it’s an excellent hip pack offering. 
Price: $109.95 / £94.99 / €109.95
Website: Thule.com
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ABOUT THE WOLF
Robert’s habitat is the Tweed Valley, Scotland, which is renowned for its root-littered enduro mountain bike trails. Robert has been developing his bike handling skills for the last 16 years. Since he was a pup, he’s been riding everything from BMX through to enduro and downhill bikes. Combining a playful style with occasional speed-focused aggression, he favors supportive bikes, and does his best to push them hard.
Rank: European Tech Editor
Size: 6’2” / 189cm | 220lbs / 100kg
Social: @robert_johnston
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