Sea to Summit Hydraulic Packing Cubes - Review 2025

Lightweight and Heavy Duty

In travel of all kinds, packing space is at a premium. You want to be able to max out the capacity of whatever you’re hauling your gear in without tearing the bag itself. Made of 70D ripstop nylon, the bags are thin and light, but with a bit of give that allows you to pack more items than you would expect. This means yes, you can bring a full-sized tube of sunscreen along with you. At 4.4 oz for the entire kit, you can avoid other similar packing triage points without undue upticks in weight.

We love ripstop nylon’s durable qualities but don’t take that as a license to pack your sword collection. Our testers were a little nervous about packing pointy sharp cosmetic scissors, and while we got away with it this time; it’s worth being mindful about what you bring along. 

Another thing to take care with are the zippers. We thought seams (another frequent problem point with products like this) felt sturdy enough, but our testers have collectively ripped enough zippers off of various pieces of gear to be wary of anything but the most robust, industrial-grade models. And you’ll want to take good care of these zips, they’re what’s keeping your gear dry.

Water Resistance

The seams and zips of the packing cube are water resistant and sturdy, providing excellent protection for your belongings. As with dry bags and other products of this nature, there’s a large window for user error.

It’s important to make sure that the zips are fully closed to ensure their water and dust resistance, it’s no fun to find your phone soaked from splashes or a dusty desert toothbrush. Fortunately, the packing cube comes with nice zipper pulls that make finagling the bag into a sealed, secure status a bit easier.

To clarify, waterproof doesn’t mean the same thing as water resistant. The Hydraulic Packing Cubes are water resistant, able to withstand various threatening spills and splashes- it is not waterproof. You, unfortunately, can’t submerge these cubes in water without repercussion, and there are very few products (see the Yeti Panga) with the mettle to resist leaking underwater.

For what it’s worth,  the Sea to Summit Hydraulic Packing Cubes do an excellent job of keeping liquids either in or out, depending on your travel needs. Stuffed in a backpacking pack, these cubes can withstand sustained, but not direct, rain. Similarly, if you’re worried about bottles or other liquid items leaking into your bag, these packing cubes provide great protection.

One of our testers noted that during a long plane ride, the bags successfully contained a leak from a shampoo bottle. We found their ability to prevent it from reaching the contents of the other luggage a compelling enough argument in itself. Thanks to the wide openings and nylon material, the leaked shampoo was easy to rinse and clean out of the cube.

Lash Points and Handles

The Sea to Summit Hydraulic Packing Cube is simple. This simplicity is what makes it such a versatile packing solution though there are a few more noteworthy features in regard to portability. The medium packing cube, for example, features a grab handle that makes it easy to carry around. The handle is attached with a low-profile design, which sits flat against the cube when not in use.

All of the cubes in the set also come with loops that allow for easy lashing. This is particularly useful when you need a water-resistant container that is easy to access, whether you’re lashing it to your kayak, SUP, or the Big River Dry Pack. The lashing loops provide a secure attachment point, giving you peace of mind that your belongings are safe and protected, though you should keep in mind the crucial difference between waterproof and water resistant.

Packing Better Together

Sea to Summit’s packing cubes are also sold in separate units as well as this set. Ours included the medium, small, and extra small versions, which made for a great balance between outdoor applicability and sizes you would reasonably want to travel with.

The clear panel on one side of the cube is helpful to quickly identify what is inside, especially if you have several cubes of the same size.

Value

Packing cubes usually come in a set, and one of the best ways to gauge value is by asking yourself how much your stuff is worth to you. In terms of quality and durability, these packing cubes are made with high-quality materials and provide excellent protection for your belongings against water, dirt, and sloppy packing.

While they may have a higher price point than other packing cubes on the market, their excellent quality and durability make them a worthwhile investment for frequent travelers or those who need reliable protection for their belongings.

Do We Recommend Them?

We think that Sea to Summit’s reputation in the outdoor industry speaks for itself and that the Hydraulic Packing Cubes are an excellent addition to their expanding catalog of gear. If you’re a backpacker who needs a little help staying organized on trail or anyone who frequents dusty or rainy environments with valuables, we think that their quality more than justifies the price.

However, for more casual travelers who just want something to keep their socks from rubbing against their floss, we’d recommend you take a look at our packing cube buyer’s guide for more of our favorites.