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  • Sea To Summit - X-Mug Collapsible Mug - Red
  • Sea To Summit - X-Mug Collapsible Mug - Grey
  • Sea To Summit - X-Mug Collapsible Mug - Lime
  • Sea To Summit - X-Mug Collapsible Mug - Royal

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  • Sea To Summit - X-Mug Collapsible Mug - Red
  • Sea To Summit - X-Mug Collapsible Mug - Grey
  • Sea To Summit - X-Mug Collapsible Mug - Lime
  • Sea To Summit - X-Mug Collapsible Mug - Royal

Sea To Summit X-Mug Collapsible Mug


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    31 Reviews


    Now you can stop drinking coffee out of water bottles.

    From morning coffee to afternoon happy hour, the Sea To Summit X-Mug pops up to hold your favorite beverage, then folds flat for easy storage. This convenient mug features an accordion-style design and food-grade silicon sides, as well as a sturdy nylon top ring to maintain shape.
    • Item #STS0070

    Tech Specs

    silicone, nylon
    16 oz
    Claimed Weight
    2.7 oz
    Recommended Use
    camping, backpacking

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Minimal Mug

    • Familiarity: I've used it several times

    Love it, the Silicon does a pretty good job of shielding your hands from heat, it packs super small, is easy to clean and comes in bright, easy to spot colors. 10 out of 10, would buy again.

    Nothing Else Measures Up

    • Familiarity: I've put it through the wringer

    This is the perfect camp mug. It packs down super small, is ultralight weight, and holds a good amount of liquid. The calibrated measuring markings inside the cup are my favorite feature, and are super handy when you need to measure out some water for a meal or hydration mix. No complaints what so ever! Get yourself one now.

    No Complaints

    • Familiarity: I've used it several times

    Super neat concept, well executed. They're durable and sturdy and you won't burn your hands if you grab it directly after pouring boiling water in it. Plus I love how little space it takes up in my pack.

    Great Mug

    • Familiarity: I've put it through the wringer

    I love this mug. It is very lightweight and compact. I use this as a bowl and a mug while on winter expeditions to save some weight. The mug is sturdy so you won't spill, and doesn't burn your hands when the hot coffee is poured fresh from the burner.

    Feel free to reach out with any questions!

    Yes for saving space!

      i got a couple of these to replace non-collapse able cups for our backpacking adventures. I am so excited to used them. They are a little difficult folding back up , but i am just glad for saving space in the packs!

      Great for Coffee or whatever!

      • Familiarity: I've put it through the wringer

      These easily collapsible cups are lightweight, durable, and easy to pack away. They're great for your backpacking cup of joe. But they've also proven their worth in splitting up Jack & Cokes at festivals, BBQs, or wherever you may go!

      Worth It

      • Familiarity: I've put it through the wringer

      I finally caved and got an X-mug and the X-bowl and they are so worth it. Anyone who backpacks knows that sometimes even small pieces can make your whole packing experience pretty tricky if they are awkward shapes (i.e. plastic mug and bowl.) It becomes obvious when you have to do it day after day. The flat collapsed shape just magically makes the puzzle pieces fit so much easier! Make packing easier, just get it.

      Great Coffee Cup

      • Familiarity: I've put it through the wringer

      I wanted a coffee cup that was lightweight and easy to stow away in my cooking kit. The X-Mug fit the bill, so I gave it a try... haven't turned back. I don't drink anything else out of it, it's simply my coffee cup. With that in mind, I can't speak to what others experienced with memory retention of past drinks that contaminate others with odd flavors. I like the fact that on a cool morning, I can warm my hands up nicely with a fresh cup of coffee by holding the mug around the silicone and the top outer ring provides a sturdy place to hold and drink the hot stuff without warming the hands at all. Sea to Summit did a great job with this one.

      Great Coffee Cup

      Doesn't Fold easily

      • Familiarity: I've used it once or twice and have initial impressions

      So far it's a decent collapsible mug. My only gripe is that it doesn't collapse as well as other similar products I've own. Overall it's a good size and I like that it has measuring units on the inside.

      Perfect cup for the slopes

      • Familiarity: I've used it once or twice and have initial impressions

      Great cup to bring skiing. Just add hot water and a pack of hot cocoa or soup, and you are set! So much cheaper than spending $3.00 for a cup of cocoa.

      It works

      • Familiarity: I've put it through the wringer

      I'm a big fan of how it collapses, huge space saver, however that comes at a price. Anything you put in the mug WILL get stuck in the folds and crevices of the cup, so it's super hard to clean well in the backcountry. Also if you have hot drinks in there it'll be hot to hold. Other than those two things I haven't had a problem and its overall a pretty good mug, but you can find better mugs for less money.

      Dirt magnet

      • Familiarity: I've used it once or twice and have initial impressions

      I love the concept. In fact, I'm positively seduced by the all of the collapsible Sea to Summit X products - they're just COOL man!

      I have a hard time with silicone though. On paper, it's so bloody neat - temperature resistant and flexible, what's not to like?

      I'll tell you - if there's any dirt, dust, the smallest mote or particle in a 2-mile radius, it'll find its way onto your X Mug.

      This is not a Sea to Summit problem, this is a silicone problem. I have a set of Snow Peak Hot Lips, they're like pot holders for your face, a lip guard for your cup - anyway, they have the same issue.

      It doesn't take much effort to clean the Hot Lips, they're quite small. Cleaning off an entire mug would get old fast.

      On the other hand, it is pretty BAD ASS the way it collapses. Most of the X line nests together in some fashion so you can assemble a Russian Doll set of cookware and dishes, which would be pretty cool.

      Tastes like barbie dolls

      • Familiarity: I've used it several times

      Taking off 1 star from an otherwise incomparable collapsing mug. Silicon will always hold onto oils and is very difficult to get clean in the backcountry. I discovered this somewhere in the Cascades, with a cup of Willamette pinot smelling powerfully of bacon, coffeee and Dr. Bronner's Lavender Magic Soap. This cup had been thoroughly cleaned - the essential oils from the soap and other foods had attached to the silicon. The smell only went away when boiling the cup in clean water an oily white residue collected on top of the water.

      Lesson learned: don't use scented magic soap.

      I have the X Shot glass I wanted for mixing drinks in camp. It does retain a little smell but a good kind in my case. But after having a few shots from the glass, I am compelled to say; "VY.P please, please stop licking your Barbie Doll.

      Awesome Cup

      • Familiarity: I've put it through the wringer

      Great cup for backpacking & traveling with. Love that it collapses so I didn't have to take up valuable pack space or hang it outside my pack. Worked well for cocktails & coffee! The silicone tends to collect some dirt but I could use the extra minerals. Cheers!

      the only dish you need for backpacking

      • Familiarity: I've used it several times

      I carried this for backpacking 4 nights in the Smokies. It worked great! It was durable and just the right size and shape for meals and drinks, so you don't need a separate cup and bowl. It collapses really well, and is extremely handy.

      Breaks easily

        This cup withstodd over 1 use! I drank coffee with it in the morning, then stowed it collapsed. Upon extending it in the evening for a beer, the ring and upper portion split. Hopefully Sea to Summit cistomer service has me covered.

        Breaks easily

        i need something collapsible to keep water warm on a small coffee mug warmer/hot plate . . . would this melt on the hot plate?

        Can you microwave your tea/coffee in this...

        Can you microwave your tea/coffee in this in your motel room the night before you leave on the trail?

        Is this offered as a set of four, or do...

        Is this offered as a set of four, or do you pay $11.90 per mug? The reason I ask is because the photo shows four colors, but the options gives you indicates that there is only "One Color." I thought maybe that's because these are sold as a set. Otherwise, you don't have a choice in color?

        Best Answer

        Nope, just one at a time. Typically the warehouse guys will just pull whatever color comes up first, but I've sometimes placed an order by phone and requested something specific. They try their best, but it doesn't always happen. As for the "one color"- it could be that one or the other is all they have in stock, or that it's the grab bag. In either case, worth a quick call to clarify.

        I love the X-Mug but mine has developed a...

        I love the X-Mug but mine has developed a small hole at one of the folds, so now it leaks. (No idea how it happened.) Any suggestions on how to repair it? Nothing seem to stick to the silicone. Or could it still be under warranty? There's no warranty info on the Sea to Summit website.

        Best Answer

        Yeah, call STS @ 303-440-8977. Ask them to replace it under warranty, since it's lifetime. The fact that it developed a hole directly on one of the folds is easily a matter of making the argument that it was due to material failure. Or, as Dean said, if you bought it here, BC will replace it unconditionally as well, maybe even faster.

        Thanks for the info Phil & Dean. I'll see if the retailer I purchased it from (not BC as I didn't know about you guys then) will take it back under warranty. The failure may have been due a thin spot that was there since day one. I would buy one again though.

        Is there a difference between the X Cup...

        Is there a difference between the X Cup and the X Mug? Volume and weight are listed as the same.

        Best Answer

        The x-mug has a 16oz (480ml) capacity and weighs 2.7 oz. The x-cup has an 8.3oz (250ml) capacity and weighs 1.6oz. The cup and the mug are also calibrated and have graduations on the side in both fractions of a cup and ml.

        Can you put this in the microwave? I am...

        Can you put this in the microwave? I am liiking for something to make tea in after riding my bicycle to school.

        Yes, it's completely safe for microwave use. Silicone has a safe temp rating of 428F/220C and your usage will never be greater than 212F/100C. The Nylon lip has a temperature rating of anywhere from 390F/199C to 490F/254C depending on the type of nylon, but the ring would be insulated by the silicone, so it's not even an issue.