A flow injection electrochemical detecting device has a base, a cover pivotally mounted on the base, and a locking device attached between the base and the cover. Gas is continuously sampled via the vent holes 28 and the vent pipe 29 from the space part inside the beverage storage tank 1 of the beverage filler and is supplied to the oxygen measuring apparatus 40. The stylus may also include an axial switch and an axial force sensor. One of the first and second lateral regions is received along one of two laterally opposing edges of the material. Upon detonation, the charge creates an explosive cutting force, or jet blast, that severs the polycarbonate material. An electromagnetically generated braking effect is applied to the trackball, which effect varies with the speed of the cursor to allow precise control of the cursor.