Rear Wiper and Washer Delete Rubber Plug Hatch OEM 280ZX

Rubber plug for deleting the rear wiper motor or the upper wsher nozzle on Datsun 280ZX.  This is a OEM Nissan plug that fits the hole very tight and has a shiny black finish.  It appears that this will be a water tight seal for the hole.  Head diameter of 30mm, fits holes size approx 20mm.