with Marelon on current boat. All original, all working fine. Only maintenance is turning them off and on every few months. For head through hulls, they clean with vinegar just like the rest of the waste system as Peg Hall recommends. I have seen recommendations for waterproof grease, but haven't needed it. Must not be strong enough to break a stem. But I still have a separate ground plane for my SSB. BTW, sure seems like most of the new boat manufacturers have gone to them as trouble free alternatives to bronze.