On the Subject of Double Digits

Wait, why are there two?

This module consists of a large button and two screens showing a digit from 0–9 each.

Take the number of batteries. Use this as the row for the table below.

Then, take the two digits in the display, and use then as the columns for the table below.

Take the numbers at the two intersections, multiply them, then take the least significant digit. This is the final value.

Press the button when the last digit of the timer is equal to this value.

Left digit Right digit
0123456789 0123456789
BATTERIES 0 8583411983 5995593892
1 9741521442 6796887597
2 1861466894 8131819172
3 1875165575 9888179555
4 9536437272 9254692573
≥5 1188631776 9257622573