These bolts are zinc plated and 3/8 BSW thread.
Eye size approx 14mm.
Overall length is approx 128mm and thread length approx 81mm. The diameter of the bolt material is approx 8.2mm.
They are supplied with two washers, one plain nut and one Nyloc nut.
See article on stay wire supported installations.
Also see :
3 and 4 hook collars
Catenary surface hook