Abstract: An automatic shutoff valve is provided. The valve is preferably constructed of a check valve (which is normally shut) and a shutoff valve which is open during static, no-flow, operation. Upon initiation of flow, even a drip flow, the check valve opens, and the pressure differential from the inlet to the outlet causes a piston in the shutoff valve to move toward a shut position. As long as the pressure differential stops before the piston closes, the shutoff valve resets to the fully open position. However, if the shutoff valve shuts, it preferably must be manually reset.

Abstract: An automatic shutoff valve is provided. The valve is preferably constructed of a check valve (which is normally shut) and a shutoff valve which is open during static, no-flow, operation. Upon initiation of flow, even a drip flow, the check valve opens, and the pressure differential from the inlet to the outlet causes a piston in the shutoff valve to move toward a shut position. As long as the pressure differential stops before the piston closes, the shutoff valve resets to the fully open position. However, if the shutoff valve shuts, it preferably must be manually reset.

Abstract: A target for use in white balancing video cameras and, in particular, video cameras suitable for endoscopic use. The target is molded from an elastomeric material having the ability to diffuse a substantial portion of light incident upon the target from a video camera. A user may use the target to white balance a video camera by placing the camera directly on the target and adjusting the light intensity of the camera's light source. In the case of an endoscopic camera, the distal tip of the scope (extending from the camera) is placed directly on the target. The user need not be concerned about aiming the camera at a selected white target and holding it a certain distance from the target.