Brand Casio Model No. F-91WG-9QDF Series Standard Gender Pria Case diameter 38 mm Case thickness 8 mm Water resistant 30 Meters/3 ATM/3 BARi Case material Plastic/Resin Case back Screw case back Glass material Mineral crystal Strap material Rubber/Silicon/Resin/Karet Clasp Buckle Calendar Perpetual Calendar Luminious / LumiBrite No Movement Quartz Movement Weight 21g Accuracy at normal temperature +/-30 seconds per month Time system Changeover between 12/24 hour formats Calendar system Auto-calendar pre-programmed to the year 2099 Measuring capacity 59'59.99" Measuring modes Net time, split time, 1st-2nd place times Battery Quartz Movement Type: CR2016 Approximately Approx. 7 years of operation on type CR2016 Others Micro Light Regular timekeeping Hour, minute, second, am/pm, year, month, date and day... on its double display 1/100 second digital stopwatch Dual time mode Daily alarm mode Hourly time signals