Strike King Coffee Tubes are scented with real coffee bean granules and coffee bean oil. This natural organic scent is incredibly attractive to fish. It causes them to hold onto the tube longer and masks human and plastic scents. Coffee granules give the tube a more natural earth tone tint that mimics the appearance of a bass' favorite prey. They are salt impregnated too! The 3-1/2'' Coffee Tube has a hollow head and is most effective when rigged with an internal tube jighead for dragging, jigging, or fishing structures with the hook exposed.