Watertight Linkage

This is a watertight linkage that was designed as part of a submarine project. It allows a 5mm rod with 8 orings [11/16" x 3/64" or 4.5x1mm] to be passed through the hull and connect to a internal motor [Servo] with no water leaking through the hull. I design and tested this for use in a submarine however I believe this linkage could be used for boats and other RC watercraft.