Its correct name should be the one for 766c96:
"Electric, Wire 12V / 4.5V with 2 Leads, 96 Studs Long with 2 Light Gray
Electric, Connector, 2-Way Male Squared Narrow Long with Center Post (x466c96
/ 766c01)"
766c28 (Inv) Electric, Wire 12V / 4.5V with 2 Leads, 28 Studs (22cm) Long with 2 Light Gray Electric, Connector, 2-Way Male Squared Narrow Long with Center Post Parts: Electric, Wire & Connector
I once pulled out the wires of my 6 copies of 7720. Their lengths differ by like
about 4cm. On the other hand, some submitters measured the length of wire including
the connectors and some excluding them. This brought up inconsistency all over
the place. I brought up this issue about 8-9 years ago but it got no where other
than one of the roadmap projects:
https://www.bricklink.com/help.asp?helpID=2476