I use this with a Barley - bag is well out of the way
https://www.spacycles.co.uk/m5b0s73p2995/CARRADICE-Classic-Saddlebag-Rack
It looks like you need metal saddle loops to hang it off? And then it straps round the seatpost but not the rails?
@LaurenceCardiff started
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I use this with a Barley - bag is well out of the way
https://www.spacycles.co.uk/m5b0s73p2995/CARRADICE-Classic-Saddlebag-Rack