Abstract: The golf club has a head and a shaft. A three axis linear accelerometer is mounted on the shaft adjacent to the head. The axis of one accelerometer is in parallel alignment with an axis of the shaft. A circuit board is attached to the shaft and the accelerometer. The circuit board includes a calibrator for calibrating at least the accelerometer with an axis parallel to the axis of the shaft. The circuit board also has a wireless transmitter. Data from the accelerometer is transferred to a processor by the transmitter. The measured velocity of the club head is displayed by a display device carried by the golfer.

Abstract: A filter support assembly (12) has a base (26) with a mounting surface (28), a rim member (34) with a flat surface (38) and post members (32) connecting the rim member to the base. Apertures (40) and the area surrounding by the rim member (34) provide air passages. One element (46) of a hook and loop connector (20) is attached to the mounting surface (28) on the base (26) by an adhesive. The other element (48) of the hook and loop connection (20) is secured to the wall (22) by an adhesive and surrounds the air inlet (50) to the housing (24). When the elements (46) and (48) are in engagement with each other, the filter support assembly (12) is secured to the housing (24) and a seal is formed between the base (26) and the wall (22) of the housing (24). A primary filter element (14) is removably secured to the surface (38) on the rim member (34). A side filter element (16) is removably secured to the support assembly (12) in a position covering the apertures (40).