In reply to msimpson73:
A few years ago I naively packed my harness, some slings, a VF lanyard and some karabiners in my hand luggage for a flight to Italy, assuming that because they weren't on the prohibited items list they should be OK.
My bag got pulled out for a search when it when through the security x-ray (at Liverpool Airport), there was lots of head scratching over the lanyard and krabs, and then a supervisor was called over. I was told that the items 'could be used as a restraint', so I wouldn't be able to take them in the cabin - they'd have to be put in the hold.
I had to take my bag back to the check-in desk (back of the queue) and had to pay for the extra item of hold baggage (£30 I think, and another queue), then rush back through security (more queues) to just about make it in time for final boarding...
Definitely not worth the stress and hassle.