The 8 buttons are labeled with cell names and cell pictures for BASO, EOSIN, MYELO, JUVEN, STAB, SEG, LYMPH, and MONO. A click sound on each touch confirms the count, and a short beep indicates you have reached 100 cells. Push the percent button at any time to automatically calculate percentages, and then keep counting as high as 999 TOTAL cells. Mistakes are easy to correct…simply push the +/- button to subtract the count, and then push the +/- button again to keep counting. Use the included power cord when in the lab, or take the Digital Differential Counter into the field by installing 2 AA batteries. Push the function (FUN) button to adjust the contrast and to monitor the battery energy. The new Digital Differential Counter will improve accuracy, efficiency, and comfort when counting cells in the laboratory.