Abstract: A watercraft for moving along a direction of movement on water includes a flexible fin with a front face and a rear face to be disposed in the water; and one end of the fin is movable along a line in a reciprocating motion along a direction transverse to the front and rear faces and the direction of movement of the watercraft, causing an opposite free end of the fin to flex back and forth in the water to propel the watercraft in the direction of movement.

Abstract: A visual locating device comprises an elongate, inherently buoyant, flexible sheet for floating on the surface of a body of water that has a longitudinal axis. At least three buoyant support struts are secured to the sheet and disposed across the longitudinal axis of the sheet such that the sheet is divided into a plurality of sections defined between respective pairs of struts. A light source is disposed on the sheet to provide nighttime visibility to the sheet. A pouch, which receives the sheet when stowed, is configured to release the sheet when immersed in water. The sheet is at least z-folded inside the pouch.

Abstract: A solar water desalination and purification device comprises an outer liquid-tight containment and an inner liquid-tight containment disposed within the outer containment. The outer containment collects liquid that forms from condensing water vapor that evaporates within the inner containment and passes through the inner containment material. The inner containment is made from hydrophobic material that allows water vapor to pass through the material as the sunlight evaporates the contaminated water within the inner containment. An inlet communicates with the inner containment for allowing the contaminated water to fill the inner containment. An outlet communicates with the outer containment to allow discharge of condensed water vapor collected within the outer containment to be used as drinking water.