The Six Moons Design Pack Liner is an inexpensive ($20) 50L waterproof bag that helps keep your backpacking gear and clothing dry when it rains. It’s seam-taped and has a dry-bag style roll-top closure, with a D-ring so you can hang it to keep your gear or food away from critters too. While it is slightly heavier than the trash compactor bags and Nylofume plastic bags many backpackers use to line their packs today, it also has added features and functionality that are useful in a wet climate. Given its exceptionally low price, it is an excellent option if you’re willing to accept a slight weight penalty over other alternatives.
Specs at a Glance
- Volume: 50L
- Weight: 3 oz – 86 g
- Closure: Roll-top
- Dimensions: 27″ x 21″ x 8″ (71 x 53 x 20cm)
- Colors: Red, green, blue, orange
- Material: Sil/PU Coated 40D Nylon Ripstop
All backpacks leak sooner or later, even ones that are seam taped and made with waterproof materials like Dyneema DCF and Challenge Ultra. The leaks occur as the result of:
- needle holes in the fabric as part of the fabrication/sewing process
- the pack fabric gets soaked through in the rain
- abrasion from the ground thins the pack fabric so it leaks
- constant folding which also weakens the pack fabric
- the pack isn’t closed properly which can happen with rolltop packs or packs with top-lid pockets
- immersion when you fall into a stream or river
Most backpackers and many hikers line their packs with a waterproof pack liner to prevent any moisture from accidentally soaking their clothing and gear, primarily as a safety measure, so that it remains dry when you need it to keep you warm and comfortable in adverse conditions. A pack liner is often used in addition to stuff sacks used for gear organization, even ones that are highly water resistant.
When evaluating a pack liner, there are a number of factors to consider:
- Volume: So you can fit all your stuff inside.
- Durability: Important if you backpack a lot.
- Weight: Definitely a factor if you’re counting your ounces.
- Price: Always a factor.
- Closure: A roll-top can be important for very wet trips.
- Ease of Repair: Liners take abuse and it helps if you can repair them easily.
- Multi-Purpose: Can it serve multiple functions to help reduce your gear weight?
- Interior Visibility: Does the liner make it easier to find your gear in a backpack?
So how does the Six Moon Designs Pack Liner stack up?
- Volume: With 50L of capacity, it provides plenty of space for the items you want to keep dry on most backpacking trips. There are many items, especially those stored in external pockets that you don’t need to keep dry like a water filter/bladder, cookpot, water bottles, etc. leaving plenty of capacity for the ones you do want to keep dry.
- Durability: The 40D Sil/PU Coated 40D Nylon Ripstop is more durable than the plastic bags that most backpackers use.
- Weight: At 3 oz, the extra weight over other alternatives is a minor tradeoff if the added functionality and durability it provides are attractive.
- Price: You get a lot of bang for the bug with this pack liner considering it only costs $20. The only ultralight backpacking gear that costs less these days is a plastic spoon.
- Closure: This pack liner has a roll-top closure so you can close it on top and water coming into the top of your backpack from wetting your gear.
- Ease of repair: Rips or holes in this pack liner can be easily repaired with tenacious tape. No special tape, patches, or glue is required.
- Multi-purpose: The D-ring on this pack liner lets you hang it, so you can protect your food bag in a shelter or hang it from a tree, or wrap your Ursack or Bear Canister with it, so they stay dry if it rains overnight. The pack liner also makes a good laundry sack for town.
- Interior Visibility: The pack liner is available in bright colors like green, light blue, and orange which make it easier to find gear inside your pack (especially if it’s black or grey).
The Six Moon Designs Pack Liner is a 50L waterproof sack with a dry bag closure that helps ensure that critical clothing and gear remain dry in your backpack when hiking in rainy weather. While it can be used by itself, many backpackers will use it to augment their existing stuff sack organization system. The advantage of using this pack liner over a trash compactor bag or Nylofume plastic bag is its durability as well as the added functionality of having a dry bag closure and hang loop. The advantage of using it over a Dyneema DCF pack liner like the Hyperlite Mountain Gear 43L Pack Liner is its price, as it’s much less expensive. But one area where it could still be improved is to add a stiffener to the dry bag closure so that it’s easier to roll up and fully compress, since without it the liner bag has a tendency to unravel if not carefully secured shut.
Disclosure: Six Moon Designs donated a pack liner for review.SectionHiker is reader-supported. We only make money if you purchase a product through our affiliate links. Help us continue to test and write unsponsored and independent gear reviews, beginner FAQs, and free hiking guides.