Dripless packing.
My observations are;overall it is a great invention.There are a few things to keep in mind. The set screws that hold the stainless ring to the shaft have been know to back out. Make sure you double the set screws AND keep the correct allen wrench close to the packing.Second, If you put the boat on the hard for the winter, "burp" the rubber boot to clear the water out. I've heard of boots freezing znd tearing over the winter.Pat McCartinInland Marine DieselLake Lanier, GA