Telescope of Smoke detectors
W303867
Main technical indicators:
1. Perspective magnification : 10 times
2. Telescope distance of observation :  10 to 500 meters
3.  lens aperture diameter 50 mm
4. Ringelmann and grade 0 ~ 5.0
5. Observational error is not more than 0.5
Main features:
hand-held observation, easy to use
modeling beautiful, clear images