The M850 digital clock chronometer has a two-button control system, setting operations are identical for both alarm and time setting. The universal time is in a 24 hour format, while local time can be set to 12 or 24 hour format. The incandescent high-contrast display is readable in bright sunlight.

Version M850-5V has orange incandescent 5V lighting and N size alkaline battery memory. This is a 2-1/4 inch front panel mount instrument. 

• Greenwich Mean Time: 24 hour format
• Local Time: 12 hour or 24 hour option
• Flight Time: Records in hours and minutes, up to  99:59, 99.99 hour option
• Flight Time Alarm: Full set range flight time
• Elapsed Time Count Up: Starts in minutes and seconds, then hours and minutes, up to 99:59 hours
• Elapsed Time Countdown: Settable from one second to 59 minutes and 59 seconds
• Elapsed Time Alarm: Activates at zero when counting down
• Incandescent Displays: Readable in sunlight
• Automatic Dimming
• Battery Type: N size alkaline Model 850
• Battery Type: AA size alkaline Model 877
• Keep Alive Current: .00004 amps
• Input Current: 0.2 Amps
• Input Voltage: 14 to 28 Volts (backlight available 5V, 14V, or 28V lighting - must specify when ordering)
• NVIS Option: NVIS Green A lighting
• Black Face Plate: Engraved Nomenclature
• Grey Face Plate: Silkscreened Nomenclature
• Weight: 5 ounces
• Warranty: 1 year