"Suspect three's been a bit of a muddle somewhere. These are described as "4.7mm, for cable diameter 7-9mm." The last bit is probably correct, but I reckon these are for flanges of thickness between 4-7mm. This matches my experience of being unable to clip them on to a girder of thickness a smidgeon over 8mm. Ah well, I'm sure they'll be useful one day on another job. Same with the "2.4mm" clips - suspect these are for flanges 2-4mm thick.
These are designed for holding round cable like SWA, SY etc. Not really that suitable for T&E, but might just about suffice."