There are times I use an Osprey hydration backpack and other times I don't want to have anything on my back. So I've adapted water bottle cages to my Thule Pack 'n Pedal rack using truss clamps. As a photographer I've used truss clamps to mount strobes, smoke machines, etc. and they are dead strong and steady. So the smaller ones work well as water bottle boss mounts. Strong and they don't rotate. I've never been happy with the strap on type which tend to shift no matter how tightly I attempt to cinch them down. Sometimes I also like to carry 40 oz bottles and purchased a cage by Specialized to hold my larger bottles with two great straps. They are the Specialized Burra Burra Stuffcage Bikepack. So when I'm going on a long ride and don't want to lug a hydration pack I switch my bottle cages to those, one on each side to hold two Camelback 40 oz bottles which are insulated. 80 oz NOT on my back makes me happy! See I love ice water and those keep water cold for a long damn time.