26-830749 drain plug seal fits the 3/8-16 drain/fill screw holes in outboard and stern drive gearcases.
Gearcase gear lube drain screw washer 830749 is made of high quality material with rubber coated stainless steel for all of Mercury, Mariner outboards and MerCruiser stern drives with 3/8-16 gearcase drain/fill screw holes, prevent gear oil leaking.
Always double check to make sure the washer has been secured when reinstalling the drain screw washer gaskets. Water could infiltrate the gearcase without it and cause catastrophic damage to the gearcase.
Keep spares on hand to assure placement after changing gear lube in gearcase.
Change this every time you change your gearcase oil. It's designed to “crush” under torque so it's a one time use washer gaskets.