A Trivision is an outdoor billboard sign that consists of triangular prisms, also called slated faces, placed inside a frame. The prisms rotate 120⁰ at intermittent intervals, each showing a new message of advertisement. As implied, three individual images, or messages, can be displayed on a Trivision which is also known as a three-message out of home advertising sign. In many cases, Trivison mechanical billboards are being replaced by digital billboards which allow operators to generate revenue from six to eight (6-8) advertisers instead of just 3.
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