Welcome to Material Lexicon, your guide to the technical fabrics used in WeitLäufer rucksacks. Here, we explain why we rely on selected fabrics such as X-Pac VX21, UltraStretch and Gridstop, and how they strike the right balance between Weight, durability and weather protection hold. Which material suits which rucksack can be read in the Ultralight Backpack Guide.
Materials in detail
Ultra 200X
Ultra 200X is the successor to the Ultra 200. A newly added Ultra-CrossPly grid increases diagonal stability and minimises the risk of delamination. The fabric consists of 67 % UHMWPE fibres; the fibre is 15 times stronger than steel on a gram-for-gram basis, a comparison drawn from the sailing industry. The material itself is 100 % waterproof and PFAS-free. With 133 g/m² remains extremely lightweight, while being more durable and dimensionally stable than its predecessor. With Agilist does the entire main subject consist of that.
X-Pac VX21
X-Pac has its origins in sailing. VX21 is a four-layer laminate (only 204 g/m²) with 210 Denier Nylon as upper material, black X-PLY® yarn for tear resistance, a 100 % waterproof polyester film for stiffness as well as an additional woven polyester layer inside. The result: high abrasion resistance combined with low weight, and the waterproof film keeps rain completely out. Proven for decades in sailing and on backpacks.
UltraStretch
Our 4-way stretch for exterior pockets: The stretch material is woven into UHMWPE threads woven in, meaning the fabric remains extremely tear-resistant and thorns, rocks or branches cause hardly any damage. Used on base, side, front and shoulder pockets.
Gridstop 210D
A ripstop fabric (132 g/m²) made from 100 % recycled nylon, reinforced with white UHMW-PE fibres. This results in a lightweight yet extremely abrasion- and tear-resistant material. On the Agilist model, Gridstop is used in the areas where the rucksack rubs against the rock: the base and the front section.
3D Mesh & EVA
Our shoulder strap pad: the 3D mesh allows air to circulate and wicks away sweat. Inside, 10 mm EVA foam provides long-lasting cushioning. The foam retains its shape, even after many trips.
X-Pac UX10
That's all 85 g/m² severe UX10Laminate combined 100 D UHMWPE-Polyester (extremely abrasion-resistant) with X-PLY® yarn, waterproof polyester film and a slightly transparent look. We use UX10 wherever a pack needs to remain as light as possible without sacrificing weather protection.
Dyneema Hybrid 50D
The 50 denier variant (CT5K.18) weighs only 104 g/m². Construction: 50 D polyester outer fabric, Dyneema® fibre mesh and waterproof polyester film. The fibre mesh makes the laminate extremely tear-resistant, whilst the polyester outer fabric withstands abrasion well. This means that even an ultra-light pack can withstand contact with rock. Just like the VX21, it has proven itself over decades.
Dyneema Hybrid 150D
With a 150 D polyester outer layer (CT9HK.18), this version ≈ 174–200 g/m² onto the scales. The thicker outer layer makes it significantly more abrasion-resistant than the 50D version. We use such heavy hybrids where a rucksack touches down and rubs: on base panels and back panels.
X-Pac RX15
RX15 is our most eco-friendly laminate: 100 % post-consumer recycled polyester with a DWR finish and a waterproof film, weighing just 196 g/m². This means you get recycled material without compromising on weight.
X-Pac RX30
Our all-round fabric (262 g/m²) made from 100% % recycled polyester – climate-neutral and abrasion-resistant. A fabric for gear that’s just as suited to everyday city life as it is to a day trip in the Black Forest.
X-Pac X11
Combines a cotton outer material with X3 laminate. Soft to the touch, yet waterproof and dimensionally stable, as well as climate neutral. At 390 g/m², it is our heaviest fabric. We use it where the pleasant feel is more important than every last gram saved.
Ultra 200
High-performance laminate from Challenge Sailcloth. Outer layer: 200 D UHMWPE fibres (67 %) & recycled polyester (33 %); inner layer: waterproof PU film. Weighing just 119 g/m², Ultra 200 combines top-class tear and abrasion resistance with sustainability (FC-free C0 impregnation).