There’s one thing you always have to get right on a trek: your duffel bag.

Think about it. First, it has to carry all your stuff, which means it can’t fall apart. Or leak. And, of course, it has to be easily carried, whether by a porter or on a yak.

That is why we suggest, for our Himalayan treks as well as our Kilimanjaro climbs, you not go cheap on your duffel.

There are three brands we like: North Face (the Base Camp Duffel), Patagonia (Black Hole), and First Ascent (Maximus). We love them all because they keep your gear dry, they are durable and strong, and they hold a lot of gear. Remember, your sleeping bag and pad will go in here, as well. Each of them can be carried like a backpack or on a porter’s head (they actually do that!), or strapped to a yak.

We do recommend you go for an XL-sized bag — or something close to 150 liters, if that is how they are measured. Another good tip: line the inside with plastic trash bags, and then to put your clothes into individual oversized sandwich bags to keep them clean and dry. Because even though the duffel won’t leak, you will have to open it, and sometimes that will be in the rain. Also, if one thing is dirty you don’t want to just toss it in with all your clean stuff.

While you’re trekking and/or climbing, you don’t want to worry about your clothing and sleeping bag being safe and dry. So don’t skimp on that duffel — go big!