I dont know how to work it I lost my Instructions I just wanted to wear it because it was new,Anyway it is a Casio edifice EFA-119

Hi Johny

You can get the instruction manual for your watch from here

regards
robotek

On mine you just press the (manual) light switch for two seconds until it beeps.

• Electro-luminescent backlight
Auto light switch, afterglow • Thermometer
Display range: -10 to 60 °C (14 to 140 °F)
Display unit: 0.1 °C (0.2 °F)
Thermometer Measurement Timing: During each even-numbered minute
*Changeover between Celsius ( °C) and Fahrenheit ( °F) • World time
30 time zones (50 cities), city code display, daylight saving on/off • 1/100-second stopwatches
Measuring capacity: 99:59'59.99''
Measuring unit: 1/100 second (the display for the first 60 minutes)
1 second (the display after 60 minutes)
Measuring modes: Single stopwatch mode: lap times, total elapsed time
Dual stopwatch mode: two independent lap time measurements, lap time differential
Memory capacity: 50 records (used for lap times and total elapsed time)
Other: Lap numbers (01 to 99); best lap time and lap number in newest log • Countdown timer
Measuring unit: 1 second
Countdown range: 100 hours
Countdown start time setting range: 1 minute to 100 hours (1-minute increments and 1-hour increments)
Other: Auto-repeat • Daily alarm • Hourly time signal • Auto-calendar (to year 2099) • 12/24-hour format • Button operation tone on/off • Regular timekeeping
Analog: 2 hands (Hour, minute;hands move every 20 seconds)
Digital: Hour, minutes, seconds, am/pm, month, date, day • Accuracy:±30 seconds per month • Approx. battery life: 3 years on SR927W X 2 • Size of case / total weight
EFA-119BK : 46.2 X 40.1 X 12.7 mm / 127g
EFA-119D : 46.2 X 40.1 X 12.7 mm / 127g