See there’s a nut missing. I’m pretty sure the bolt is M5, but a normal nut won’t fit in the slot, and there’s nothing to stop it spinning freely if I could get one in. Could someone have a look and measure the nut that should be there. My best guess is it should be a thin square type, with 8mm sides and about 2.5mm thick. Could anyone confirm so I can track one down. I bought it second-hand and it was gone before I got it. Cheers.

It is a square bolt as you say. I could check the size tonight if needs be but its a tight fit into that slot (Tight enough that 90% of the time it doesn’t fall out when you remove the bolt). You would be better of measuring the slot in the clamp (cut down a bit of paper till you get the right measurement)

Just been googling a bit more. Reckon it’s one of these, but it’d be nice to be sure as they have a £5 min order, I’ll have to google some more to get one cheaper.

Thin square nut?

Shameless bump for evening shift.