i can see three on the frame... but two on the seat? what'd he have, a holder or something bolted to the rails of the saddle that held water bottles off the back?
surprised the guy doesn't just carry a 3L camelbak on him! then again, i find 'em uncomfortable for rides over 50km.
Now that I look, Profile sells dual-bottle brackets that fit on the seat rails, as well as brackets that fit on the seat post.... so that would be,, ehh,,, 3 frame, two stem, two seat, and two on the seatpost.
Nine bottles.
Assuming you can use both the seat and seatpost brackets at the same time.
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As to "why not just use a bladder", I understand that many competitive riders prefer bottles, so they can keep track of how much they are drinking at any point in time.
Also with bottles, some can be energy mix and others plain water.
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