I use an older Camelbak RimRunner with a capacity of 24L. While the Klim RF uses is nice cuz of how the S2 case has its own slot, it doesn't have enough capacity for the stuff I want on a ride. I looked at it pretty hard and decided against it. And even with the bigger RimRunner, I wear a Klim fanny pack to make even more room in the Camelbak so its not jammed. If I don't take S2, then I don't need the fanny pack....so what I take depends upon what I'm planning to do.
One thing that I wanted was a good way to carry the beacon in an accessible location and I found this perfect pouch on Azon:
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As you can see, I added a wrist lanyard off an old camera for security of the beacon (in case I drop it). The pouch nicely attaches to the camelbak strap via some velcro wraps I got:
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Heres what my RimRunner looks like. I got one just like this when they were brand new prolly 15 years ago, I still have it, but this one I got on ebay last year, in brand new condition!
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A key requirement for me in a hydration pack is 3L capacity. The RimRunner fits the bill.
As for what all I carry, its everything I need for a day long dirt bike ride. I'm prolly forgetting some things, but in the main compartment, S2 in its case with 2 batteries, jacket, pump, tube or plug kit, hat, TP, first aid kit, lunch, and in the small compartment, smaller stuff like wallet, keys, inReach, energy bars, map and other misc stuff. I have room to put in a 3rd and prolly 4th battery if desired but with just the case and what I've listed, its pretty easy to take the case in and out once its place is created when you insert everything.
With the orange elastic cord, you could theoretically stuff a jacket or something in there, and maybe clip it to the pack itself for extra security.
I could put even more in this than I currently do. Part of the motivation in using it is it gets weight (tools) down lower.
If all you're gonna do is have S2 follow you, you don't need the controller. Its cheap and some phones (maybe most these days) don't fit in the cradle. I glued a strip of drywall corner protection to the cradle so the phone wouldn't pop out, and I had a pretty small phone (in comparison to most these days). If you're gonna fly S2 like a regular drone, the controller is easier to use than just flying with a phone/app and ya can tilt the gimbal.
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