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Most Recent Reviews
The loops which are located at the top for use with the supplemental straps are made too small to use said straps. Mountainsmith knows this and will send out supposedly a fix. Have not received the fix yet. Beware.
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Hipbelt Size: 48 inGender: Unisex Weight: 1.8 ozPack Type: Backpack Capacity: 30 lbPack Volume: 40 litersColor: Phantom Body Material: 210d EXTREEMA Recycled Nylon Ripstop Hydration Compatible: No Fabric/Material: Recycled 210d nylon SD oxford/Nylon 100D x Span 840D stretch mesh Age Group: Adults Pack Loading: Top

Code: XV-BP0-MOU202-21-50441-44

MPN: 21-50441-44

UPC: 757894331580

Product No Longer Available

Product Info for Mountainsmith Zerk 40L Backpacks

Countless hours, thousands of miles, a hundred beers, and one giant beard later and we are proud to introduce the ZERK 40. Co-designed with The Real Hiking Viking, a renowned thru-hiker with thousands of hiking miles under his belt, the ZERK 40 pack stands alone as the ideal combination of weight, durability, comfort, and accessibility.image

Co-designed with The Real Hiking Viking, a professional hike-really-long-distances-really-quickly-er, the ZERK 40 was born out of a need for an ultralight pack that can withstand the thousands of miles per year that The Real Hiking Viking already covers. We wanted to make sure that it would allow him to go farther, to hike longer, and to work more efficiently on the trail. Over the course of 2 years of development, the ZERK 40 went through 4 iterations and over 5,000 miles of testing on the Wind River High Route, the Colorado Trail, The Tetons, and more.

Features of Mountainsmith Zerk 40L Backpacks:

  • 1.5in removable waistbelt;
  • A large main compartment holds up to 40 liters of gear;
  • Roll-top closure with side compression SR buckles. Opposing SR buckles for self-closing roll-top;
  • Side compression straps for securing load throughout the entire pack;
  • Large side water bottle pockets with angled openings to easily remove and insert items while on the go;
  • Expansive front mesh pocket for hauling bulky gear;
  • Large mesh side stash pockets with angled openings for easy reach;
  • Reflective screen printing and cord loops for low light visibility;
  • Front cord loops can be configured with a bungee cord (included);
  • Removable interior laser cut frame sheet (EVA Atilon) allows for rigidity and airflow;
  • Extra-wide shoulder straps with adjustable sternum strap (includes safety whistle);
  • 4 Large mesh front pockets on shoulder straps (2 per side);
  • EVA foam padded shoulder straps;
  • Removable bear canister and accessory over-top webbing straps with SR buckle closure;
  • Front panel bungee attachment system;
  • Dimensions: 18.5x11.75x5.75 in;
  • Waistbelt max 48 in;
  • Torso range 16-19 in;
  • Volume: 40 L/2440 CI with fully extended collar;
  • 32L/1952 CI with roll-top compressed;
  • Weight: 1lb 13oz with accessories, 1lb 11oz without accessories

Package Contents:

  • Mountainsmith Zerk 40L Backpacks

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Mountainsmith Zerk 40L Backpacks Unavailable & Discontinued Models

List of Unorderable Models

  • Mountainsmith Zerk 40L Backpack, Phantom, 21-50441-44 , MPN: 21-50441-44 , UPC: 757894331580 , Code: XV-BP0-MOU202-21-50441-44
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