they have adapters for adding water bottle cages to the handlebars as well and some clamps / adapters for adding a second water bottle cage to the seattube. i've tried a few setups on my older bikes (without bottle cage mounts on the seattube) and didn't love any of the options i tried. i recently modified some old toptube cable clamps to hold a bottle cage - i added some very thin electrical taoe underneath so it doesn't mar the frame paint. works well so far