The fenders ( boat fender) are used for tugs, barges, workboats and pilot boats as side belting and protective fenders against heavy rubbing, brushing forms. The D type fenders display a higher energy absorption capacity, thus minimizing deface contact. Theses fenders can also be mounted on anchor belts.
The type of fender that is most suitable for an application depends on many variables, including dimensions and displacement of the vessel, maximum allowable stand-off, berthing structure, tidal variations and other berth-specific conditions. The size of the fender unit is based on the berthing energy of the vessel which is related to the square of the berthing velocity.