B07RX92XMV ArenaGear Sports Timers

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Perfect for timing show jumping and other events (Track and Field, sprints, 40-yard dash, etc.) Accurate to 1/1,000 of a second. Time is displayed on your phone, (useful when you miss the announcement after your ride – we all done that!)
No Cables – Completely wireless for quick set up. RM-501-ShowJump includes both Start and Finish gate and 4 tripods.
Time to the 1/1,000 of a second (0.001) is displayed on any iPhone, iPad or Android phone or tablet with Bluetooth within 400ft, maximum distance between Start and Finish gates is 400ft. Optical range of the laser beam is up to 200 feet. Eye-safe infrared beam, won’t hurt human or animal eyes even if looking straight into the beam
Very easy to use. Unlimited number of phones can receive the time. Keeps time of the last 500 runs in memory. Any phone within 400ft can receive the time if running our free app

Battery Life – 150+hrs on a single set of AA batteries