double-action only

double-double wargame

double-tap strike / double tap strike

double-action

double-action fuze

double-action pull

double-action revolver

double-action trigger system

double-pull trigger action

For Official Use Only (FOUO)

eyes only

night only computer generated image

FEDCON (Federal Employees and Contractors only)

once-only approach

admittance by authorized credentials only

interact with character mode files only

Core Only

electrically erasable programmable read-only memory (EEPROM)

Failsafe only

Hexadecimal digits only, 0-9, A-F

Only arm after successfull EDT handshake

Only flash firmware if you are fully aware what you are doing.

Only MULTI mode currently supported

Return altitude (meters) - only applies in Fixed Altitude mode

RP (increment only)

RPY (increment only)

Heading are only shown when magnetometer is in use

This sets if the TX only beeps one-time versus playing a startup song

Only use to compensate for really bad tunes

officers' eyes only    

ears only

for your ears only

after-action review / after action review (AAR)