Climbers (and cavers etc) use karabiners which are a little bit like the
clips Bill mentions. But some karabiners have screw gates (as Alan P
mentions). These screw across the gate (sic) to stop them opening by
accident. Climbers etc who want to grow old use ones with screw gates
when their safety depends on the gate staying shut.

A question for Bill: do all your cable ties stay flexible that long?
I'd always assumed (albeit for no good reason) they would fail after
flexing a lot especially in low temperatures.

--
Robin
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