The newest 2011, Speeder-2000 Chronograph from Guarder is one of the nicest portable chronos out there. Capable of measuring MPS, FPS, and Energy in joules as well as Rate of Fire. Internal rechargeable battery and tripod mount aids in portability and functionality. Got a gang of friends coming over for a back yard skirmish? Afraid someone might be shooting a bit too hot? set them straight with this high quality Chronograph from Guarder!