Coolest Bottle in the World

Hey guys,

I want to share a personal project that I just completed and get some feedback on it. Below is a short value proposition and link to the project.

Value Proposition: For an athlete who wants to carry any combination of fluids, (pre/post workout drink, electrolytes/water, etc) Contender is a sports drink bottle, which allows the athlete to do so in just one bottle. Unlike a hydration belt or other bottles, Contender makes carrying two fluids easy in a compact design that simplifies going to the gym, running, cycling, and other activities where two fluids may be beneficial. This is possible through a unique bottle design that seals two cells containing fluid separately and enables the athlete to chose their drink by turning the lever on a valve, opening the cell to the straw.


Interesting function. Reminds me of the Gel Bot -

I’ve seen the Gel Bot, but didn’t quite follow how it worked until I watched that video. Thanks for sharing!

I like your approach a lot. You have a pretty clear path outlined on how to use and also manufacture. The bottle looks expensive to make but for the right consumers it could be huge.

Daniel Stearman
Product Designer at Hydrapak

I love it. If I did any sort of sports I’d probably get one.

The use of the buttress thread and ball valve design is great… did you have a past life at a water equipment manufacturer?

@Singletrack: Thanks for the input! I think the minimum viable product could do without the clear section to indicate fluid levels and the form could be altered for easier manufacture. I’m not sure what the best way to manufacture a bottle with a dividing wall is though; perhaps blow molding in two halves and pulling out a divider while material is cooling or just adhere them?

@Azrehan: I appreciate the kind words and no, I have no past life as a water equipment manufacturer. Haha, I have looked at how other water bottles are being made though.

I think you have done well with the project but have a few questions. First would be trying to fill up the bottle and not have the and the second is that I wonder how much fluids you lose from the cut away for the hand in the side and if holding it there would warm the fluids up too quickly.

When I saw your project I thought of this I saw the other day and thought you might be interested.​es-and-water

Great project. Just a suggestion, or food for thought: how about instead of turning the lever, we simply turn the mouthpiece? Or as an alternative, raise the mouthpiece a certain height for one, then raise further for the other.

An interesting suggestion, but have you ever drank from a sport bottle?

I really like this idea. When i bike I bring 2 bottles of water. However, i have ‘salted out’ several times and needed something with some electrolytes. It would be nice to have this (although now I have the mix packets in my bag). However, I am not 100% sold on your idea yet due to the cleaning aspect. I will usually ride on consecutive days, so the bottles wont go into the dishwasher. I just hand wash them quickly. I dont see how that would easily be done with the divider in there. And when i put any sort of sports drink in, I really have to clean it to remove any remaining stuff that will taint the bottle for the next ride. I must not be the only person that goes through this same process of cleaning considering that the clean bottle exists.

@mas2: Could you reword your first question, I wasn’t able to follow it. I think the recessed section would cut into the volume some, but some indentation is necessary so that it still fits into a bike cage. As long as the volume allows for around 12oz of each fluid, it would be sufficient. If the bottle was manufactured with a double-walled construction, it wouldn’t warm up to quickly. I frequently run with a Camelbak Podium bottle and have cool water the whole time.

@awjj: I think the lever would be part of the mouthpiece construction, it also serves as a nice indicator as to which fluid is open. The second idea you mentioned is similar to the way the Gel Bot works which I hadn’t considered, but is probably feasible. Thanks for your input.

@j2cervin: I understand the cleaning aspect, I do the same thing. Unless you are comparing it to the clean bottle though, I think it would be pretty similar to most bottles on the market. I could probably benefit by watching some people hand wash bottles though; I doubt I’m as thorough as others. I just kinda rinse it out as soon as I get back, shake in a little dish soap, rinse again, and put it on the drying rack. If you try and get any kind of brush in there, it could be problematic. Thanks for bringing that up; I’ll put some more thought into it.

I wanted to comment on the separation since you brought that up as a question. The separation was my biggest concern with your design. As it sits I do not think it is feasible because the outer bottle would normally be blow molded there for pretty difficult to add a full length separation. It might be possible to blow molded it in hales and then bond them together but this is a very big question. Also Awjj brings up a great point and would probable work better to have the mouth piece rotate instead of the outer lever. I know the Podium bottle does the lever lock and it is pretty cool how it works but I think because you have a lot going on it would be better to do a mouth piece lock. Bottles are pretty difficult to make. They need very exact tolerances and even standard expansion and contraction of materials cause problems. When I started at Hydrapak I was really surprised how difficult it really is to create a bottle. We have just finished a double wall insulated bottle like the Podium and it was really difficult to pull off. That being said I am assuming this is a student project and for that I think you have done an excellent job of showing your idea and indicating construction methods. Your thinking is good and presentation is strong so judging it like that I think it is quite successful.

Sorry, just saw that I didn’t actually finish the sentence. What I was trying to say was that I think it would be hard to pour liquids in without accidentally getting them in the wrong side unless they used something like a funnel. Particularly as the valve makes the separation wall lower inside the bottle.

Daniel, thanks for elaborating a bit. I can imagine how difficult bottles are to make, especially when you begin to consider things like insulation. I am fortunate to have someone like you give feedback on the project. This was a small personal project that I did to start getting some sports related projects into my portfolio (I’d like to design products related to triathlon, etc) so your positive comments were definitely good to hear!

@mas2: That is something that could be an issue. I imagined it being used primarily for fluids that both start with water and an electrolyte tab or powder is added to one side which could be a little easier. Maybe there could be a way to just expose one side at a time though? Thanks for the comment, I’ll think about that one some more.

The 4-bottle drink belt is just about the dorkiest thing I have ever seen