Since you have both horns you won't need pics from me to see if there's a physical difference. Can you see a physical difference? Is there a manufacturer's stamp on them?
So here's what I was able to find out from FAST regarding the part numbers:
There are 2 horns. One is a high note, while the other is a low note.
HORN ASSY - ELECTRIC HIGH
Part Number: 25610-60U00 (supersedes to B5610-60U00)
Prod.M/Y:0889-0790
Prod.M/Y:0790-0293
HORN ASSY - ELECTRIC HIGH
Part Number: 25610-67U60
Prod.M/Y:0293- and
Prod.M/Y:0293-0694 (HICAS models)
HORN ASSY - ELECTRIC LOW
Part Number: 25620-60U00 (supersedes to B5620-60U00)
Prod.M/Y:0889-0790
Prod.M/Y:0790-0293
HORN ASSY - ELECTRIC LOW
Part Number: 25620-67U60
Prod.M/Y:0293-
You also might be interested in checking out one of my old threads:
Anyone have a non-Q45 horn? Ferrari, Hella, Fiamm, Stebel, Wolo
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