GPS LightLock Astronomical Timer, Astronomic Time Clock Switch, Wire-In. Self-Programming w/ onboard GPS. 15 Year Warranty. Made in USA. The world's only self-programming Astronomical Timer. US Patent 8,816,842. Internal GPS sets the date, time & location automatically. Auto-synchronizing & maintenance free for life. Outperforms other astronomical timers at a fraction of the cost. 15 year performance warranty - unmatched in the industry. Also available in Twist-Lock model. Please see ASIN B010G370D0. Lightning Arrestor & Surge Protection included.