Mountainsmith Day Lumbar Pack

A legendary trail pack, updated for 2026.

For more than 40 years, the Mountainsmith Day Lumbar Pack has been a trusted choice for hikers and outdoor enthusiasts who want serious carrying capacity without the bulk of a traditional backpack. Now updated for 2026, the Day continues its function-first legacy with durable construction, smart organization, and versatile carry options.

With 13 liters of gear-swallowing capacity, the Day is ready for much more than hiking. Carry it around your waist on the trail, sling it over your shoulder for commuting, or use it for disc golf, tailgating, birding, travel, and everyday adventures.

The spacious main compartment includes a padded tablet sleeve, while the bright yellow interior makes it easier to locate your gear. Reinforced side pockets accommodate water bottles up to 32 oz / 1 liter, and the zippered front pocket with key clip keeps frequently used essentials close at hand. Smartphone-compatible zippered waistbelt pockets provide additional convenient storage.

Mountainsmith’s Delta Wing Compression System helps keep your load secure and close to your lower back, while the FreeFlow padded back panel adds comfort during long days. When you want a different carry option, simply attach the included 1.5-inch padded shoulder strap. For hiking with heavier loads, the Day is also compatible with the Strapette or Strapette EVO shoulder harness systems (sold separately) for backpack-style carry.

Whether you're spending the day on the trail, or simply need a versatile bag for everyday adventures, the Mountainsmith Day is built to keep up.

Key Features

• 13-liter capacity with a spacious main compartment
• Interior foam-padded sleeve for tablet carry
• Smartphone-compatible zippered waistbelt pockets
• Removable, tuck-away waistbelt with forward-pull adjustment
• Delta Wing Compression System for load adjustment
• FreeFlow padded back panel
• Reinforced side bottle pockets fit bottles up to 32 oz / 1 L
• Inner Sanctum™ zippered mesh pocket for valuables
• Zippered front pocket with key clip
• Dual bottom compression straps for additional gear
• Removable 1.5" padded shoulder strap
• Headphone/hydration hose port
• Security webbing loop inside the main compartment
• Bright yellow interior lining for improved visibility
• Compatible with Strapette and Strapette EVO shoulder harnesses (sold separately)

Built for Everyday Adventure

The Day is constructed from durable 420D DD Dobby Nylon, with a 150D high-density poly liner and reliable YKK® zippers. It's designed to handle the wear and tear of regular outdoor use while remaining comfortable enough for all-day adventures.

Mountainsmith states that there are no intentionally added PFAS in this item.

Specifications

• Volume: 13 L / 793 cu. in.
• Dimensions: 13" L × 12" H × 6" D
• Weight: 1 lb 11 oz / 0.77 kg
• Waistbelt Fit: 28–48"
• Suggested Load: 8–10 lbs
• Materials: 420D DD Dobby Nylon; 150D high-density poly liner
• Zippers: YKK®

Find the Mountainsmith Day at Scot’s Sporting Goods in Estes Park, Colorado. Locally owned and located near the entrance to Rocky Mountain National Park, Scot’s Sporting Goods offers outdoor gear and local expertise for visitors and residents alike.