WATER SKI TRACTOR “DOLPHIN” WITH ELECTROMAGNETIC COUPLING OF SKI
WATER SKI TRACTOR “DOLPHIN” WITH MECHANICAL COUPLING OF SKI, MONOSKI AND WAKEBOARD
DEVICE FOR ATTACHMENT OF TOWING CABLE TO OPENING DEVICE
TRAWL BOARD WITH FLOW ACCELERATOR TO INCREASE LIFTING CAPACITY
METHOD AND DEVICE FOR ENSURING FISHING WITH THE HELP OF A FISHING VESSEL