VSMD66694 Dual-Color Emitting Diodes Vishay VSMD66694 Dual-Color Emitting Diode combines the technologies of a standard red LED with an IR emitter with 660nm and 940nm peak wavelengths. The diode is based on SurfLight™ technology, providing high radiant power. Vishay VSMD66694 Dual-Color Emitting Diode is housed in a 2mm x 2mm x 0.87mm square PCB surface-mount package to save board space for smaller applications. Typical applications include wearables, health monitoring, and pulse oximetry.