Pot of propellor grease from New Zealand.
At Marchwood, fouling is a really bad problem. We have tried everything, without much success. This grease, is applied to the plain metal of the propeller after the blades have been warmed with a heat gun. It lasted about 2-3 months. The problem is that on a short mid season liftout it is difficult to reheat the propellers. I got lazy and reverted to antifouling, which is no better.