With a cast metal housing each one is marked Hi or Lo like the original. Each one is tested before packaging and has adjustment screw for tuning. 1967 – 1968 LH with Integral Air Con has a different bracket because it mounts on the condenser bracket.
Also, 1967 – 1968 Horns will fit 1971 – 1973, but to be exact the horn needs to be turned on the bracket for correct direction of horn mouth.
High Pitch = RH
Low Pitch = LH