1)Timing: In normal status, press M button to access the timing mode. If the display to the time does not show zero, then press S button to stop timing. Press R button to reset the display back to zero. 2)Start timing Press S button to start timing. Press S button again to stop timing. (Press S button repeatedly to start or stop timing). Press R button to reset the display back to zero. 3)Split mode Press S button to start timing. Press R button to display the first period time; press R button again to stop the time. Then press R button to display the second period time. Press S button to stop the time. Press R button to reset the display back to zero. 4) Lap mode Press S button to start timing. Press R button to display the first period time; press S button to stop the time. Press R button again to display the second period time. Press R button again to reset the display back to zero. 5)Time, calendar and alarm display In normal status, press S button to display month, day and week. Press R button to display alarm. 6) Time and calendar set up In normal status, press M button 3 times to access the time set up mode. Second, weed and time will flicker at the same time. Press R button to adjust minute, hour, day, month, week and second settings (A/P is 12 hour format, A is A.M., P is P.M., H is 24 hour format). Press S button to change the numbers (hold the S button and the numbers will go faster). After adjusting, press M button to return to normal status. (p.s. Second can only be adjusted 00) 7) Alarm setting In normal status, press M button twice to go to the alarm mode. Hour and week will flicker at the same time. Press R button to choose minute and hour settings. Press S button and adjust the time. After adjusting, press M button to return to normal status. In normal status, hold the R button and press S button repeatedly, the alarm sign will display/disappear that means alarm is on/off. 8) Warning Avoid humidity. Do not expose the sport stop watch in direct sun light for extended period of time. Avoid corrosive materials. Do not use it under too much or too low humidity environment.Specification: Package Weight One Package Weight 0.01kgs / 0.02lb Qty per Carton 140 Carton Weight 9.30kgs / 20.50lb Carton Size 40cm * 30cm * 30cm / 15.75inch * 11.81inch * 11.81inch Loading Container 20GP: 740 cartons * 140 pcs = 103600 pcs40HQ: 1719 cartons * 140 pcs = 240660 pcs