This is a Streamlight Flashlight known as the Microstream, model 66601.
Streamlight's popular MicroStream is now available in a rechargeable model. Ultra-compact" this personal light" which fits in the palm of your hand or comfortably in your pocket" provides unparalleled performance for its size.
Features:
Multi-function push-button tail switch
Removable pocket clip
Durable, anodized aluminum construction, Unbreakable polycarbonate lens