The composition of products: laser by emitting tube core, condenser lens, sleeve of three partsSent to users when the three parts have been assembled, lens focal length is adjustedAnd has good use super glue, users connected to 4.5 V dc power supply can workMake it.

Product description: ideally (no dust, no smoke, no any blockage), laserThe transmission distance is unlimited.This laser under the condition of the air quality is higherTo 20 ma, working current, the transmission distance can reach more than 1 km, inGenerally cloudy night, casually exposure to 500 meters outside of the objectThe very visible;For close distance, even if the sun in the daytime, in the roomOn the road, buildings outside is clearly visible

Working voltage: 4.5 v 51 resistance work time: a long (because there is no accurate test)