omron relays

[allconfusedat39]

what exactly do thje numbers mean

i have a 4EP-81950-00 relay

which i understand is a yamaha part number

after that i have stamped on the relay

G8R-30Y-F

then 25Z5D2

its an 11 pin relay of which their are a few around - however the numbering tends to be different so am curious as to the significance this makes?

if you know would be good to hear what it all means