Saddle mounted hydration?

Im trying to find something for fairly cheap to mount two water bottles behind the saddle on my road bike. I don’t want to spend 50 bucks, but i do want it to be functional, doesnt have to be pretty… Anyone have anything or have any advice? The stuff i have looked at has mixed reviews and I dont want to waste any money…

$17: 65g and you’re done: http://www.trisports.com/tasacl.html

If it’s a road bike, you already have 2 mounts on the frame…that’s a lottta water.

I just got a Profile Design Aquarack for a couple of euros on eBay. Fits a standard 27.2mm round seatpost and mounts 2 standard cages.

Good for training, wouldn’t race with it though - there are more aerodynamic solutions for race hydration.

I dont have any on the frame right now. I just wanted to do two behind the saddle and thats it.

minoura dual cage is another option
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