Abstract: A generator comprising an interface and a control circuit is disclosed. The interface is to electrically couple to an ultrasonic surgical instrument comprising a switch. The switch is configurable between a first switch state and a second switch state. The control circuit is to provide a continuous drive signal to the ultrasonic surgical instrument based on the switch being in the first switch state. The control circuit is to provide a pulsed drive signal to the ultrasonic surgical instrument based on the switch being in the second switch state.

Abstract: A swimming pool cleaning device having a first portion and a second portion obliquely offset from each other. The first portion has a clip assembly for adapting into a conventional swimming pool cleaning pole. The second portion has a hollow with a large aperture and a slit aperture where the hollow is gradually converged towards the slit aperture. The second portion also has a nozzle assembly extended to the large aperture for adapting a conventional water hose such that water from the water hose can flow through the large aperture into the hollow. People can use the cleaning pole to control the underwater movement and orientation of the cleaning device. Pressurized water supplied by the water hose will pass through the converged hollow of the cleaning device and spurt out of the slit aperture. This pressurized and intensified water current directly cleans the submerged swimming pool surfaces.