We are factory seller, V1,V2,V3,V4, GPS version are produced by our own factory! High quality guaranteed! Features: CE approved wireless lap timer Accuracy of 1" interval/0.01" Easy to use and install Fast shipping! Technical copy manual: This EZLAP V1 lap timer is an exciting item for most users and dealers. Some functions that will not be used by most users have been removed, so the production cost reaches the limit. The system consists of a transmitter and a timer (signal receiver); One transmitter can work with all lap timers that are on the same frequency. Two rear AA batteries are recommended for the transmitter. Lap timer (receiver): UP: LCD display shows one lap backward; DOWN: LCD shows one lap ahead; Sum : summary; Slowest lap time, fastest lap time, total time and average lap time; CLR: a two-second press will clear the memory and turn on the signal receiver, so the timer will start counting when it passes the signal wall; short press will stop the timer from counting and the LCD display will change to the last record; Transmitter: The transmitter has a laser pointer and a signal relay to build a signal wall; It is powered by 2 AA batteries; Lasts for 5 hours continuously; It is suggested to turn off the transmitter during idle to save power; Note: Batteries should be replaced after 5 hours of use to avoid weak signals; Remove the batteries from the box during long idle; It is prohibited to point the laser at the eyes, keep the product away from children.