Model: UltraFire WF-502B (Cree R2) - Features a Cree XR-E R2-WC LED emitter - Powered by 1 x 18650 or 2 x 3.0V/3.6V CR123A batteries - Maximim voltage input: 8.4V - 5-mode tail cap clicky switch with state memory: Hi > Mid > Lo > Strobe > SOS - State memory memorizes the previously used mode and returns the light to it when you turn the light on - 250 lumens maximum brightness (manufacturer rated) - 1000mA current output digitally regulated driver circuitry (manufacturer rated) - 50 minutes estimated total runtime (manufacturer rated) - Coated glass lens with aluminum textured/OP reflector