I checked out a pair of the composite Lezyne side loading ones and they held on so tight that it was crushing the bottle and I didn't see how I'd be able to easily get it out on the go. After some searching I got the Arundel Sideloader and Othersideloader which I believe only come in carbon BUT have two mounting holes. This worked out well since I needed a little extra room for bottles mainly for the seattube mount because of my frame bag. Let me know and I can post a picture if you'd like one.