This 8-Leaf Light Shaping Barndoor is optimized for the Elation KL PAR FC fixture. It has an 7.5-inch industry-standard size that's compatible with many other theatrical lighting fixtures.
barn door: a hinged opaque panel mounted on a light fixture used to screen light from an area or from the camera. "A word to the wise – in any other context than lighting, don't leave your barn door open."
