The Play Action Rod Knob is made of soft rubber to provide comfort to the abdomen from gimbaled rods. Can be used to replace rod butt caps. Soft rubber has high co-efficient of friction to prevent slippage when rod butt is placed on deck or abdomen. It's useful for many things including: changing baits, removing weeds or fighting fish. With a slight twist the Rod Knob can easily be removed if a larger belt is needed. The tapered and ribbed design inside the neck fits most rod butts. Recommended line class is 10-30 lbs.