The 4SF000 series bearings are suitable for all types of hull material. This bearing type combines a very simple installation with a very smooth operation under all circumstances as the bearing will always be aligned to the rudder shaft. The bearing consists of an aluminium outer housing with an inside sphere turned out. A one piece delrin ball is located in the sphere and is sealed to the outer housing by an O-ring. The inner housing is pushed inside the delrin ball and also sealed with an O-ring. This construction creates a watertight situation between the rotating inner housing and the fixed outer housing. The disadvantage of this bearing is the fact that top of the bearing, the rudder stock and locking ring stand out above deck. If this is not acceptable, one should choose the bearing type 4S000Z or use it under deck.