Ten-Digit Display, 1" High Solid-Segment Digits, IRIG-B Interface, Integrated AOS/LOS Timers, Oak Enclosure. Our IRIG-B Clocks display days, hours, minutes and seconds. Our AOS/LOS Clocks have dual Timers that are synchronized to an IRIG-B Master Clock time source. The AOS Clock indicates the hours, minutes and seconds until the acquisition of the signal. The LOS Clock indicates the minutes and seconds until the loss of the signal.