Drain plugs

[Neutron]

Can anyone verify for me, is the transom bilge drain plug different from all the other compartment plugs.

Reason why i ask is i have been taking on a little water and narrowed it down to the transom drain plug.
After looking at all the plugs the one coming from the tank area that is in the forward wall in the engine compartment was very different from all the rest.

The one on right is the same everywhere and was in transom. The one on left ( which has more threads and makes more sense for the transom) was in engine bay

 

[haknslash]

My transom plugs are like the one on he right.

 

[Noko]

The ends of the plugs are different so the one on the right should stay in. The one on the left is made so you can remove it. But other than that, a plug is a plug.