I use Cobra security cables, the 5m ones, and a good padlock on my seats.
I am sorry to hear of your problem. Paul at PD high seats has had to make some all in one high seats, as opposed to his multi sectioned ones, because one of his better known customers kept getting her high seats nicked. They are even nicking manhole covers round here. Anything the pikeys can flog to the scrapman has to be well secured or it's gone!
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