Basic alarm clock & battery operated clock - This clock is powered by 4 x AA alkaline batteries only (not included), which can keep Constantly Big 1.2'' LED digit time display for more than 12 months.

Our alarm clock offers 8 adjustable sounds that can ... 【USB Charging Port and Battery Backup】- Conveniently charge your smartphones, tablets, or other 5V electronic devices with the built ...

These were chunky dual-in-line devices containing clock and non-volatile RAM chips, a crystal, and a lithium battery. The battery was good for about a decade, which was fine for most PCs of the ...