Broadcasting, studio and theatrical supplies are used in the planning and production of television shows, radio programs, movies, films, plays, concerts, and other audio or video recordings. They include video production consoles, theatrical lighting, theatrical curtains, and broadcast booths. Suppliers may serve a variety of industries, or specialize in one or more applications. Often, providers of broadcasting, studio and theatrical supplies are located in areas with television and movie studios, radio stations and sound stages, and related facilities. There are many different types of broadcasting, studio and theatrical supplies. Products for television shows, movies, plays, and films may include period costumes and TV or movie sets; lighting products such as light dimmers, stage lights, and spotlights; video production equipment such as cameras and monitors; and sound equipment such as microphones and microphone stands. Broadcasting, studio and theatrical supplies for public service announcements, public relations (PR) campaigns, and corporate media is also available. Broadcasting, studio and theatrical supplies include many different types of video production equipment. Examples include complete console systems, broadcast and production consoles, editing and graphics consoles, data and security devices, and accessories. Complete video console systems may feature moveable turrets with a multiple track design for the placement of liquid crystal display (LCD) monitors. Video broadcast and video production consoles are modular devices that consist of components such as production and master consoles. Video editing consoles are used in the non-linear editing of film. Related products such as audio workstations are also available. Data and security products for broadcasting, studio and theatrical supplies include command and control rooms and technical operations centers. Broadcasting, studio and theatrical supplies for audio applications are used in a variety of recording and programming applications. Products include audio mixers, audio monitors, speakers, amplifiers, portable sound systems, signal processors, surge protectors, audio cables, headphones and headsets, sound testers, and wireless communications devices. Audio mixers may be powered or non-powered. USB mixers for studio recording are a common type. Audio monitors are used by sound engineers and other personnel who specialize in audio quality and control. Speakers are specified according to size and wattage. Types include column speakers, ceiling speakers, and wireless speakers. Broadcasting, studio and theatrical supplies such as amplifiers are also specified according by watts. Features include independent channel volume controls.