A retractable antenna is provided that includes a body having an orifice, a whip retractably coupled to the body, at least one follower disposed about the whip, and a cam disposed about the orifice. Herein, the support members are detachably attached to an interior periphery of the cylinder to support the support plate, on which the vibration absorption member is mounted and is arranged in contact with a backside surface of the drumhead to absorb vibration of the drumhead whose surface is being struck by a drumstick or else. A membership account number and a payment corresponding to a requested amount of a service offered by the vendor are received from the customer at a point-of-sale. Said other intermediate image includes the wavelength located beyond the first sub-band.