1.5" x 2.0" x 0.5" size. Powered by 4 x LR1130 1.5volt batteries. Display is removable. Momentary push button powers the ATMEGA328P loaded with Arduino firmware to save batteries. On board DS3231 Real Time Clock keeps the time.
Arduino analog pins 1-6 and digital pins 7-13 can be directly accessed through the female header placed above the LED display. Can easily be programmed by using the FTDI or ICSP ports on the bottom. 2 red push buttons set the time.