An impact tool has a slidable hammer that is driven by hydraulic oil under pressure inside a chamber. A method of collimating the monocular devices, so that the binocular device is collimated. The linear ion trap comprises a plurality of rods which define an interior trapping volume which has an axis extending longitudinally. The nosepad also has first and second ends and a substantially inverted-U-shaped body. The cross-shaped support frame is equipped with a central tube at the central part of the cross-shaped support frame.