Katy Stickland tests the submersible rucksack-style Sea to Summit Hydraulic Pro Dry Pack, subjecting it to journeys by sea, air and rail over a seven month period

Product Overview


  • Submersible and airtight so contents are kept bone dry
  • Comfortable to wear, even with heavy loads
  • Heavy duty material, which has barely been marked despite all the use


  • Does not fold up small although the shoulder straps can be removed
  • Price (RRP £350 upwards) but does come with lifetime guarantee


Sea to Summit Hydraulic Pro Dry Pack: long term test

I have been testing the Sea to Summit Hydraulic Pro Dry Pack for the last seven months, during which time it has been on numerous sailing and dinghy trips, been through the hands of airport baggage handlers, squeezed into tight train luggage racks and carried for miles while walking from stations and airports to hotels and holiday homes.

The bag I tested has a 50-litre capacity, more than enough space to pack for a week afloat; my husband, John and I managed to pack all our clothes for a 9-day trip to Cornwall in the summer.

Larger sizes – 75L and 100L – are available but I found the 50L had more than enough room.

A man carrying a rucksack dry pack

The padded shoulder straps are adjustable and the bag, with the chest strap, is comfortable to carry. Credit: Katy Stickland

Being a bad back sufferer, the rucksack-style nature of the Sea to Summit Hydraulic Pro Dry Pack was appealing to me; the padded, adjustable shoulder straps which extend down the back panels also made it incredibly comfy to carry.

There is also a chest strap which meant even carrying heavy loads was not a problem. The straps also have multiple lash points and can be removed.

The sides have thick-ish webbing grab handles which were useful for clipping to the dinghy; and these would be of real benefit if the bag was carried on a kayak or canoe, especially for camping paddle adventures.

The zip on the Sea to Summit Hydraulic Pro Dry Pack

The TIZIP prevents water from entering the bag. Credit: Katy Stickland

In addition to how comfortable it was to carry, even fully packed, the real selling point of this bag is that it has a pressure tested waterproof TIZIP and RF-welded seams which meet IPX8 submersion rating to four metres below the surface.

Each bag comes with TIZIP MasterSeal, a lubricant which is applied to the end of the zip to ensure the bag remains watertight at depth. It is also important to keep the zip clean and free of any debris.

I have applied the MasterSeal twice since I started using the bag.

Sea to Summit Hydraulic Pro Dry Pack on a boat

The webbing grab handles on the side of the bag are great for securing it to the dinghy. Note the side pocket is not waterproof, unlike the main compartment. Credit: Katy Stickland

Without access to scuba gear, it was hard for me to test the claim that this bag is fully submersible up to four metres.

Instead, I decided to try the next best thing, which was weighing down the bag and submerging it into my friend’s 1m deep Wim Hoff-style ice tank and leaving it for 20 minutes.

I inserted a piece of clean, dry brown cardboard in the bottom of the bag so any water ingress could be detected.

Sea to Summit Hydraulic Pro Dry Pack

A piece of cardboard and weights were used to test how waterproof the bag was. Credit: Katy Stickland

Sinking it for 20 minutes is far longer than the dunking the bag would get if it fell off a tender or boat, but I wanted to see how truly waterproof the Sea to Summit Hydraulic Pro Dry Pack was.

After 20 minutes, I removed the bag; the cardboard was bone dry, and not a drop of water had seeped in.

However, I did find out that the bag’s side pocket is not waterproof (nor is it claimed to be), which is worth remembering in case you decide to put any electronics, like a phone, in there.

Sea to Summit Hydraulic Pro Dry Pack

The main compartment of the bag was bone dry after being submerged in water for 20 minutes. Credit: Katy Stickland

The bag is made from 1000D high tenacity double-sided TPI-laminated fabric, which is designed to be “super-tough” and “ultra-durable”.

Given it has been squashed into tight spaces and subjected to airport baggage handling, the bag has stood up brilliantly as there is barely a mark or crease in the material; in fact, it still looks nearly new.

Straps on a dry bag

The shoulder straps can be removed for ease of stowing. Credit: Katy Stickland

My only tiny criticism is that because of the toughness of the material, it is hard to fold the bag really flat which would be a plus when sailing on a small boat, although the shoulder straps are removable. With a starting price of £350, it is also expensive, but comes with a lifetime guarantee.

For me, the versatility of this bag means it is the only one I will ever need to own.

Available in 50L, 75: and 100L and in Jet Black or Picante Red

Buy it directly from Sea to Summit here.

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