THIS LITTLE BUGGER TELLS THE NEUTRAL LIGHT WHEN ITS TIME
TO LIGHT UP.
AND EVEN IF YOU DON'T HAVE A NEUTRAL LIGHT , ITS NEEDED TO KEEP OIL FROM GUSHING OUT WHEN THE ENGINE IS RUNNING.
Well this is 10mm diameter and total overall length end to end is 33mm.
Length of the plastic part is 21mm not counting anything brass.