Guest - Not logged in 

Reviews > Stuff Sacks > Dry Bags > SealLine Blockerlite Dry Bag > Test Report by Nancy Griffith

November 26, 2017



NAME: Nancy Griffith
EMAIL: bkpkrgirlATyahooDOTcom
AGE: 51
LOCATION: Northern California, USA
HEIGHT: 5' 6" (1.68 m)
WEIGHT: 128 lb (58.10 kg)

My outdoor experience began in high school with a canoeing/camping group which made a 10-day voyage through the Quebec wilds. I've been backpacking since my college days in Pennsylvania. I have hiked all of the Appalachian Trail in Georgia, Tennessee and North Carolina. My typical trip now is in the Sierra Nevada in California and is from a few days to a few weeks long. Over the past few years I have lowered my pack weight to a lightweight base weight of 15 lb (6.8 kg) while still using a tent, stove and quilt.



SealLine BlockerManufacturer: Cascade Designs, Inc.

Year of Manufacture: 2017

Manufacturer's Website

2.5L: $15.95
5L: $18.95
10L: $21.95
15L: $23.95
20L: $26.95

Listed Weight: --------------------Measured Weight:
2.5L: 1 oz (28 g) ------------------1.0 oz (27 g)
5L: 1.2 oz (33 g) ------------------1.2 oz (34 g)
10L: 1.6 oz (44 g) ----------------1.5 oz (43 g)
15L: 1.8 oz (52 g) ----------------1.8 oz (51 g)
20L: 2.1 oz (59 g) ----------------2.0 oz (57 g)

Sizes (W x L x H):
2.5L: 2.8 in x 5.3 in x 9.5 in (7 cm x 13.5 cm x 24 cm)
5L: 3.4 in x 6.5 in x 12 in (9 cm x 16.5 cm x 30 cm)
10L: 4.4 in x 8.3 in x 14 in (11 cm x 21 cm x 36 cm)
15L: 4.9 in x 9.3 in x 16 in (12 cm x 23.5 cm x 41 cm)
20L: 5.5 in x 10.4 in x 19 in (14 cm x 26.5 cm x 48 cm)

Colors Available: Blue, Coral, Orange, Yellow
Colors Tested: Blue (20L), Coral (2.5 and 5L), Orange (10L), Yellow (15L)

Made in China


Package FrontPackage BackThe Seal Line Blocker Lite Dry Sacks are ultralight, waterproof dry sacks with a rectangular shape to help make packing more efficient. They are made from PVC-free material of 20D Silicone Polyurethane-coated nylon and have a roll-top closure that buckles.

The top of the closure is quite stiff on both sides for a tight double seal. The seams are fully-welded with no-stitch seams that are claimed to be 50% stronger than sewn seams.

Each size of the dry sacks comes in a variety of four different bright colors with a large SealLine logo near the bottom of the sack. There is a tag inside the sack that notes the size of the sack.


My initial impression was that the dry sacks seemed much as I expected based on the website. I received a variety of colors but with four colors available and five dry sacks, my smallest two sizes are the same color. So, for the most part, it will be easy for me to identify which sack is which size just based on the color. Nice.

leashEach sack came in a cardboard sleeve with an ingenious leash to hold the sack to the packaging until purchase. Rolled up in each sack was an instruction leaflet in four languages.

Next I noticed just how light these sacks are. The top closure is substantial and seems heavy-duty but the sack fabric is so lightweight that the overall sack is really light.

I really like the bright colors that won't tend to blend in with the colors in nature. That way I'll be able to easily find the sacks both in camp and in my backpack.

The sizes seem to provide options for my backpacking needs. The smallest sack would be nice for my phone, headlamp, note pad and other small items. The 5L sack would fit my kitchen cookset and stove nicely. The 10L sack is just right for my double-wide quilt and two pillows and as luck would have it, the sack matches my quilt color. That will make it easy to remember. The 15L sack will fit plenty of clothing and can be rolled down if it is too large. And the 20L sack should fit our double-wide winter sleeping bag which happens to be the same color as the sack too!

I don't like to use pack covers so having waterproof sacks inside my backpack is for me the best way to protect my gear.

The sacks seem to be round based on my being used to round stuff sacks, but when I examine the bottom closely it is a rectangular shape which should make my gear want to fit in that way too. We'll see how that works once I get packing.


instructionsThe instruction leaflet gives instructions on how to properly close the sack by closing the top, rolling it over three times and snapping the buckle.

The care and use instructions say that the sacks should be cleaned and aired out after each use. They are to be stored dry, inside and out. Life of the sack can be extended by padding any sharp corners to minimize wear of the fabric. Insect repellents and solvents are bad news for the fabric and should be kept away.

The roll-down closure is not guaranteed to remain waterproof if the sack is submerged so sensitive electronic equipment, cameras, etc. need to be stored in a more sealed case for this environment. They are intended for rain, splash and spray and not for submersion.

Lastly, there is a limited warranty for life against manufacturer's defects in materials and workmanship.



5L and 10LDuring this test period I carried the sacks on one eight-day backpacking trip and three overnight trips.

Pacific Crest Trail Section P, Trinity Alps, Castle Crags Wildernesses, Northern California: 8 days; 100 mi (161 km); 2,157 to 7,426 ft (657 to 2,263 m); 52 to 90 F (11 to 32 C); clear to partly cloudy skies with evening thunderstorms and hail; pack weight 27 lb (12 kg)

White Pocket, Vermillion Cliffs National Monument, Arizona: overnight; 4 mi (6.4 km); 5,646 to 5,732 ft (1,721 to 1,747 m); 42 to 77 F (6 to 25 C); clear to partly cloudy skies

Hackberry Canyon, Grand Staircase-Escalante National Monument, Utah: overnight; 5 mi (8 km); 6,100 to 6,225 ft (1,859 to 1,897 m); 48 to 83 F (9 to 28 C); clear sunny skies

Great Basin National Park, Nevada: overnight, 4 mi (6.4 km); 9,800 to 9,900 (2,987 to 3,018 m); 34 to 52 F (1 to 11 C); clear to dark heavy clouds


10LOn the longer backpacking trip, I used the 10L bag to carry clothing for both my husband and me and had plenty of room for a week's-worth of clothes including spare shirts, socks, underwear and down jackets and base layers. I did not carry our rain gear inside the dry bag.

I packed our double-wide quilt and two pillows into the 15L bag which fit inside easily with room to spare. The 2.5L sack was for electronics and small items like my headlamp, phone, battery pack, cord, note pad, wallet and other small trinkets.

I used the 5L sack for miscellaneous things such as my first-aid kit, toiletry bag and reading material. I would normally use it for my kitchen gear but I didn't cook on this trip. On the overnight trips, though, I did use the 5L sack for the cookset, stove and kitchen gear such as cups and spoons.

The sacks have a rectangular shape so they seem to fill the corners of my backpack better than typical round sacks. And they stack better inside the pack with the more squared-off corners. The difference isn't amazingly noticeable because it seems that soft items such as clothes and the quilt still round out the sack. And any hard items naturally determine the shape such as my cooking pot.

2.5Lfood hangingOn the trail I also used the 15L sack overnight to hang food out of the reach of bears. The sack did a great job especially on the evenings where we had heavy thunderstorms. No water got inside. We didn't encounter any rain while hiking other than after we were in the tent. So, I didn't get any experience with keeping water out of my gear inside my backpack.

I loved the smallest, 2.5L sack for carrying small items and electronics. It fit easily in the top pouch of my backpack and provides peace of mind that my critical gear would be protected in case of rain. I also put those critical items in it on the Hackberry Canyon hike where we were hiking in water (in the river with extremely slippery banks) the entire way. Fortunately, the water level was low but again it was nice to know that these items were protected in case I slipped and fell.

I like the bright colors and can easily find what I'm looking for based on the color of the sack.

The durability seems good. I haven't seen any wear, breaches of water or abrasions. I have been careful when using the sacks for harder or sharper items such as my square foil pot lid to make sure that it isn't poking into the sack.



green lake LTRI used the Seal Line dry bags for two more backpacking trips and multiple day hikes. I also used them in Hawaii for snorkeling and kayaking.

Overnight Trips;
Lassen National Park, California: 4 days, 15 mi (24 km); 6,695 to 10,463 ft (2,041 to 3,187 m); 27 to 54 F (-3 to 12 C); mostly clear skies with one very breezy day

Green Lake, West Lake, Par Value Lake, Hoover Wilderness, California: 3 days, 12 mi (19 km); 8,030 to 10,300 ft (2,448 to 3,139 m); 38 to 64 F (3 to 18 C); clear skies with some moderate wind; some off-trail scrambling to upper lakes

Day Hikes:
Kuilau/Moalepe Trails, Kauai, Hawaii: 7.5 mi (12 km); 580 to 1,149 ft (177 to 350 m); dirt and slippery red mud conditions

Four Hikes in Volcanoes National Park, Big Island, Hawaii from 2.5 to 3.6 mi (4 to 5.8 km); sea level to 3,900 ft (0 to 1,189 m); wet and dry lava rock, soil and decomposed lava


beach LTR
Great at the beach!
The Blocker Lite Dry Bags continued to work well for backpacking. I found them easy to pack with gear and easy to pack inside my backpack. I didn't encounter any heavy rain conditions on the trail so I wasn't able to assess their waterproof ability while hiking all day in the rain.

I took the bags on our three-week trip to Hawaii hoping I could get some more testing in and found them to be extremely useful! Since there were often heavy downpours, we frequently got stuck out hiking, swimming or walking. It didn't matter much since the temperatures are so warm, but I always had things with us that I wanted to protect. I used the bags nearly every day for keeping electronics, wallets and keys dry and for keeping some clothing dry. I especially liked the bright colors for snorkeling so that I could keep an eye on our valuables on the beach while we were in the water. The bags worked fantastically for keeping out sand too which was an added bonus that I hadn't even considered.

I ended up using the smallest bag the most often and the largest bag the least. So that turned out to be consistent among all bag sizes; the smaller the bag the more I used it.

LTR wear
Light wear and stains
LTR breach
Droplets coming through
The durability seems good compared to any other dry bags that I've owned. There are a few areas where the logo is wearing off or is stained by something and the small sack has ink marks where my pen obviously was put away with the tip still exposed.

I can't see any wear areas or compromised seams so I decided to perform my own water test on the two most-used bags at home. I turned them inside-out and filled them with water and hung them up to see if any water came through. The smallest bag had four droplets coming through. One was at a seam and three were through the fabric. This sack had seen the harshest test since I routinely stored wallets, keys, phones and other small hard items inside without protecting the bag from them by wrapping in a cloth.

I then tested a bag that I had used quite often but only for clothing. This bag had no breach whatsoever and was completely intact. Overall, I'm impressed with the durability and retention of the waterproof properties. These are excellent bags especially given their very lightweight fabric.


The Seal Line Blocker Lite Dry Sacks are ultralight, waterproof dry sacks in varying sizes that are rectangular for efficient packing.

Light weight
Variety of colors


This concludes my Long-Term Test Report and this test series. Thanks to Cascade Designs and for the opportunity to test these sacks.

This report was created with the Report Writer Version 1. Copyright 2017. All rights reserved.

Read more reviews of Cascade Designs gear
Read more gear reviews by Nancy Griffith

Reviews > Stuff Sacks > Dry Bags > SealLine Blockerlite Dry Bag > Test Report by Nancy Griffith

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

If you are an avid backpacker, we are always looking for enthusiastic, quality reviewers. Apply here to be a gear tester.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson