A reversible thong-type undergarment which includes a single unseamed cloth having opposed first and second panels secured thereto wherein each of the panels may have different color combinations andor designs. More specifically, when 100 parts by weight of a polyorganosiloxane base polymer and 1 to 100 parts by weight of a reinforcing silica are mixed together, 0. As the fluid heats up, it may change phase from a liquid to a gas.