Black Diamond Pursuit 15 vs Mountainsmith Zerk 20 UL Daypack
Quick take: The Mountainsmith Zerk 20 UL Daypack carries more (20 vs 15 liters); the Black Diamond Pursuit 15 is lighter (1.19 vs 1.75 lbs).
Which one to buy
A frame sheet is the one thing the Mountainsmith has that the Black Diamond doesn't, and at the same $179.95 it changes what you can carry. The Zerk 20 UL's removable EVA/Atilon sheet gives it a suggested 20 lb load, or 30 lb when pushed, in a 20 L bag that extends to 23 L. Its body is Robic nylon with a UHMWPE grid and a poly liner, more abrasion-resistant than typical daypack fabric. The Pursuit 15 is frameless and 15 L, so everything it holds hangs from your shoulders. For heavy water days and full layer kits, the Zerk is the better daypack.
The Pursuit is lighter at 1.19 lbs (the Zerk drops to 1 lb 6 oz stripped), has Z-pole storage for folding poles and an external hydration pocket. Warranty is a tie: both makers cover defects for life.
Fit could decide it. The Zerk is built for a 15-19 in torso, so taller hikers may find it short; the Pursuit is one size too, and Black Diamond doesn't say what back it was cut for, so try both loaded. Snacks ride on the shoulder straps either way, since neither belt has a pocket.
Black Diamond Pursuit 15
Best for short, fast hikes with folding poles, where low weight and pole storage matter more than load-carrying.
Mountainsmith Zerk 20 UL Daypack
For day hikers with a 15-19 in torso who carry heavy water and layers and want a frame sheet to put it on their hips.
| Spec | Black Diamond Pursuit 15 | Mountainsmith Zerk 20 UL Daypack |
|---|---|---|
| Price | $179.95 | $179.95 |
| Rating | — | — |
| Type | Daypack | Daypack |
| Frame Type | Frameless | Internal Frame |
| Capacity | 15 L | 20 L |
| Weight | 1.19 lbs | 1.75 lbs |
| Max Load | Not specified by the manufacturer | 20 lbs suggested (30 lbs for demanding use) |
| Torso Fit | One size | 15-19 in; waistbelt 28-48 in |
| Material | 100% recycled body fabric | 100D/210D Robic nylon X-Grid Extreema (UHMWPE) ripstop with UTS coating, high-density poly liner |
| Back Panel | Padded contact back panel (construction not detailed by the maker) | Airflow EVA foam over a removable EVA/Atilon frame sheet |
| Adjustable torso | No | No |
| Ventilated back | No | No |
| Raincover included | No | No |
| Hipbelt pockets | No | No |
| Removable lid | No | No |
| Hydration sleeve | Yes | Yes |
| Fits BV500 bear can | No | No |
| Warranty | Black Diamond Practical Product Lifetime Warranty against defects | Mountainsmith lifetime warranty against material and workmanship defects; repair or replacement at Mountainsmith's discretion |
Pros & cons
Black Diamond Pursuit 15
- ✓Dedicated Z-pole storage keeps folding poles accessible without taking the pack off.
- ✓External hydration pocket means the reservoir can be refilled without unpacking.
- ✓100% recycled body fabric.
- ✓Lifetime warranty against defects.
- ✗$179.95 for 15 L is expensive; many 15-18 L hiking daypacks sell under $100.
- ✗One size only.
- ✗The waist belt is trimmed, with no pockets mentioned.
- ✗No raincover, ventilated back or stated load rating.
- ✗15 L is tight for cold-weather layers.
Mountainsmith Zerk 20 UL Daypack
- ✓A removable frame sheet in a 20 L daypack lets it carry up to a suggested 20 lb, or 30 lb when pushed.
- ✓UHMWPE-grid Robic body with a poly liner is more abrasion-resistant than typical recycled-polyester daypacks.
- ✓It drops to 1 lb 6 oz with the frame sheet and belt removed.
- ✓Hydration sleeve included, and YKK zippers throughout.
- ✗$179.95 is high for a 20 L daypack; mainstream framed daypacks of this size often cost $100-150.
- ✗The waistbelt is a removable 1.5 in webbing strap with no pockets.
- ✗One torso range (15-19 in) only, so taller hikers may find it short.
- ✗No raincover or ventilated back.
Black Diamond Pursuit 15 vs Mountainsmith Zerk 20 UL Daypack: common questions
Does the Zerk 20 UL's frame sheet make a real difference?▾
It's why Mountainsmith can suggest 20 lb loads, or 30 lb for demanding use, in a 20 L pack. The Pursuit 15 is frameless with no stated load rating. Strip the Zerk down and it drops to 1 lb 6 oz.
What happens if a seam fails on either pack?▾
Both makers cover defects for life. Black Diamond backs the Pursuit 15 with its lifetime defects warranty, and Mountainsmith covers the Zerk 20 UL against material and workmanship defects for life, repairing or replacing it at its discretion.