Manfrotto 200SC1 Suction Cup/Spike 679B, 680B, 558B
The Manfrotto 200SC1 Suction Cup/Retractable Spiked Foot is an optional upgrade made to fit the "D20" tube, found upon the 679B and 680B monopods.
The suction cup increases the monopod's effective footprint by ~20x, yielding a significant increase in stability when needed upon certain surfaces. Retract the rubber cup to reveal a steel tip which provides a firm footing on soft ground.
This monopod foot can be removed and replaced at will, even in the field.