Size of festoon bulbs in my 2100SD

[Sled600]

I have a 2004 2100SD. It has 2 seperate nave lights on the bow (Red - port, Green-Stbd ....obvioulsly)

I want to replace the incandescent bulbs with LED bulbs.

Looking online, there are a bunch of different lengths.

I am not near my boat for another couple weeks, so I am hoping to order these and have them when I get home.

The question.....Does anyone know how long the bulbs are in the nav lights on this boat?? They aren't big, but my memory can't distinguish the difference in millimeters.... :-)

thanks in advance!!!!

Rocky