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Sea to Summit X-Cup Collapsible — Specs & Analysis
Manufacturer specifications, compared against every other camp accessories in our database. We do not test gear in the field — we measure, verify, and compare.
The X-Cup is a 250ml collapsible cup with a rigid polypropylene rim and flexible silicone body. It collapses flat to half an inch tall, taking up virtually no space. Useful for morning coffee, measuring water, or a small drinking vessel when you don't want to dirty your cook pot.
Who Is the Sea to Summit X-Cup Collapsible Best For?
Bikepackers who want a dedicated drinking cup without any pack space penalty. If that describes your riding style, the X-Cup Collapsible should be at the top of your shortlist. It sits in the Camp Accessories category alongside 10 other products we track.
How It Compares
At 45g and $12, the X-Cup Collapsible is 5g heavier than the lightest option in this category (the Rawlogy Cork Massage Ball at 40g). It's also the most affordable option available.
The price-to-weight ratio comes in at $27 per 100g — a reasonable middle ground between performance and value.
What We Like
- +Collapses nearly flat — takes up zero usable space
- +Rigid rim makes drinking comfortable
- +Heat-resistant silicone handles hot drinks
Watch Out For
- −250ml is small — only good for espresso-sized portions
- −Silicone can retain flavors between uses
- −Flexible body makes one-handed drinking awkward
The Bottom Line
We haven't scored the Sea to Summit X-Cup Collapsible, and neither has anyone else we can cite. It's here for its verified specifications and dimensions, which is what the fit tools run on — a score is an editorial judgement, and we don't hand one out until someone has a basis for it. What this page can tell you is measured: 45g, $12, and how both sit against every other camp accessories product we track.
Weight checked against the manufacturer on 18 August 2026 — see the source.
Specifications and dimensions come from the sources listed above. Where a page draws on first-hand riding, it says so.
How it compares
Against the 11 camp accessories we hold published specs for.
At 45g the X-Cup Collapsible is lighter than 9 of 10 alternatives we track, which makes it among the lightest we track. The category median is 76g.
At $12 it undercuts 10 of 10 of them, against a median of $40. That works out at $27 per 100g — below the $29 median for camp accessories.
Weight and price come from published specifications. Cost per 100g is a blunt measure — it rewards light gear and says nothing about durability or whether the thing works — so treat it as one input, not a verdict.
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