Visible Designer Emitter Five Pack - works with any Xantec connecting block.<br /> The 283D Blink-IR Designer Emitter contains a small Infrared LED housed in a miniature, designer styled, black appearing, injection molded plastic shell. Unlike other emitters, the 283D emits visible red light in addition to IR (infrared) control signals when activated by IR commands sent to it by IR receivers or other Xantech controllers. The 283D is designed to be installed directly on the IR sensor window of the controlled device.</p>