When over ATS with MTI CLX it is used for Oceananic Clearance.
/PIKCLYA.OC1/CLX 0832 220611 EGGX
CLRNCE 602
DLH436 CLRD TO KORD VIA
ERAKA
RANDOM ROUTE
60N020W 61N030W 61N040W
60N050W TOXIT
FM ERAKA/0959 MNTN F380
M085
END OF MESSAGEE823
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PIKCLYA = ATC Center Facility 0832 = HHMM UTC Time Stamp of Oceanic Clearence ? 220611 = YYMMDD Date Stamp of Oceanic Clearence ? EGGX = Departure Airport DLH436 = Flight Number or Callsign KORD = Destination Airport ERAKA = Oceanic Route Entry (Way)Point TOXIT = Oceanic Route Exit (Way)Point FM = Flight Management 0959 = UTC Time over Entry (Way)Point MNTN = Maintain F380 = Flight Level (380=38000ft) over Entry (Way)Point M085 = Mach Number (085=0.85) over Entry (Way)Point