CoolLED has launched the pE-100, a fluorescence LED source. The device offers instant on/off and 0 to 100% intensity controls. It can be used on all microscopes with an external light source port for epifluorescent or transmitted light applications. Users can select their desired wavelength from more than 20 LED wavelengths. An optional cable is available for external transistor-transistor logic trigger. The instrument features quiet operation, fast switching, active cooling and no hazardous materials.