If they're chromes then they'll have different coloured ball ends a well as the blue silk.
You need to get a look under that bridge cover somehow.
'80 Rick 4001. '84 Fender Power J Special, '05 USA Jazz, '11 USA Precision, M Miller Jazz. Peavey T-40, Zoom B3. GB ShuttleMax 12.0, GB Uber410, fEARful 212.