diff --git a/src/mesg_num.jl b/src/mesg_num.jl
new file mode 100644
index 0000000..355b00c
--- /dev/null
+++ b/src/mesg_num.jl
@@ -0,0 +1,217 @@
+# Take from MesgNum.java class in SDK.
+
+module mesg_num
+
+FILE_ID = 0
+CAPABILITIES = 1
+DEVICE_SETTINGS = 2
+USER_PROFILE = 3
+HRM_PROFILE = 4
+SDM_PROFILE = 5
+BIKE_PROFILE = 6
+ZONES_TARGET = 7
+HR_ZONE = 8
+POWER_ZONE = 9
+MET_ZONE = 10
+SPORT = 12
+GOAL = 15
+SESSION = 18
+LAP = 19
+RECORD = 20
+EVENT = 21
+DEVICE_INFO = 23
+WORKOUT = 26
+WORKOUT_STEP = 27
+SCHEDULE = 28
+WEIGHT_SCALE = 30
+COURSE = 31
+COURSE_POINT = 32
+TOTALS = 33
+ACTIVITY = 34
+SOFTWARE = 35
+FILE_CAPABILITIES = 37
+MESG_CAPABILITIES = 38
+FIELD_CAPABILITIES = 39
+FILE_CREATOR = 49
+BLOOD_PRESSURE = 51
+SPEED_ZONE = 53
+MONITORING = 55
+TRAINING_FILE = 72
+HRV = 78
+ANT_RX = 80
+ANT_TX = 81
+ANT_CHANNEL_ID = 82
+LENGTH = 101
+MONITORING_INFO = 103
+PAD = 105
+SLAVE_DEVICE = 106
+CONNECTIVITY = 127
+WEATHER_CONDITIONS = 128
+WEATHER_ALERT = 129
+CADENCE_ZONE = 131
+HR = 132
+SEGMENT_LAP = 142
+MEMO_GLOB = 145
+SEGMENT_ID = 148
+SEGMENT_LEADERBOARD_ENTRY = 149
+SEGMENT_POINT = 150
+SEGMENT_FILE = 151
+WORKOUT_SESSION = 158
+WATCHFACE_SETTINGS = 159
+GPS_METADATA = 160
+CAMERA_EVENT = 161
+TIMESTAMP_CORRELATION = 162
+GYROSCOPE_DATA = 164
+ACCELEROMETER_DATA = 165
+THREE_D_SENSOR_CALIBRATION = 167
+VIDEO_FRAME = 169
+OBDII_DATA = 174
+NMEA_SENTENCE = 177
+AVIATION_ATTITUDE = 178
+VIDEO = 184
+VIDEO_TITLE = 185
+VIDEO_DESCRIPTION = 186
+VIDEO_CLIP = 187
+OHR_SETTINGS = 188
+EXD_SCREEN_CONFIGURATION = 200
+EXD_DATA_FIELD_CONFIGURATION = 201
+EXD_DATA_CONCEPT_CONFIGURATION = 202
+FIELD_DESCRIPTION = 206
+DEVELOPER_DATA_ID = 207
+MAGNETOMETER_DATA = 208
+BAROMETER_DATA = 209
+ONE_D_SENSOR_CALIBRATION = 210
+TIME_IN_ZONE = 216
+SET = 225
+STRESS_LEVEL = 227
+DIVE_SETTINGS = 258
+DIVE_GAS = 259
+DIVE_ALARM = 262
+EXERCISE_TITLE = 264
+DIVE_SUMMARY = 268
+JUMP = 285
+SPLIT = 312
+CLIMB_PRO = 317
+TANK_UPDATE = 319
+TANK_SUMMARY = 323
+DEVICE_AUX_BATTERY_INFO = 375
+DIVE_APNEA_ALARM = 393
+INVALID = -1
+
+# All message numbers and their string variants.
+MESG_NUM_MAP = Dict(
+    FILE_ID => "FILE_ID",
+    CAPABILITIES => "CAPABILITIES",
+    DEVICE_SETTINGS => "DEVICE_SETTINGS",
+    USER_PROFILE => "USER_PROFILE",
+    HRM_PROFILE => "HRM_PROFILE",
+    SDM_PROFILE => "SDM_PROFILE",
+    BIKE_PROFILE => "BIKE_PROFILE",
+    ZONES_TARGET => "ZONES_TARGET",
+    HR_ZONE => "HR_ZONE",
+    POWER_ZONE => "POWER_ZONE",
+    MET_ZONE => "MET_ZONE",
+    SPORT => "SPORT",
+    GOAL => "GOAL",
+    SESSION => "SESSION",
+    LAP => "LAP",
+    RECORD => "RECORD",
+    EVENT => "EVENT",
+    DEVICE_INFO => "DEVICE_INFO",
+    WORKOUT => "WORKOUT",
+    WORKOUT_STEP => "WORKOUT_STEP",
+    SCHEDULE => "SCHEDULE",
+    WEIGHT_SCALE => "WEIGHT_SCALE",
+    COURSE => "COURSE",
+    COURSE_POINT => "COURSE_POINT",
+    TOTALS => "TOTALS",
+    ACTIVITY => "ACTIVITY",
+    SOFTWARE => "SOFTWARE",
+    FILE_CAPABILITIES => "FILE_CAPABILITIES",
+    MESG_CAPABILITIES => "MESG_CAPABILITIES",
+    FIELD_CAPABILITIES => "FIELD_CAPABILITIES",
+    FILE_CREATOR => "FILE_CREATOR",
+    BLOOD_PRESSURE => "BLOOD_PRESSURE",
+    SPEED_ZONE => "SPEED_ZONE",
+    MONITORING => "MONITORING",
+    TRAINING_FILE => "TRAINING_FILE",
+    HRV => "HRV",
+    ANT_RX => "ANT_RX", 
+    ANT_TX => "ANT_TX",
+    ANT_CHANNEL_ID => "ANT_CHANNEL_ID",
+    LENGTH => "LENGTH",
+    MONITORING_INFO => "MONITORING_INFO",
+    PAD => "PAD",
+    SLAVE_DEVICE => "SLAVE_DEVICE",
+    CONNECTIVITY => "CONNECTIVITY", 
+    WEATHER_CONDITIONS => "WEATHER_CONDITIONS",
+    WEATHER_ALERT => "WEATHER_ALERT",
+    CADENCE_ZONE => "CADENCE_ZONE",
+    HR => "HR",
+    SEGMENT_LAP => "SEGMENT_LAP",
+    MEMO_GLOB => "MEMO_GLOB",
+    SEGMENT_ID => "SEGMENT_ID",
+    SEGMENT_LEADERBOARD_ENTRY => "SEGMENT_LEADERBOARD_ENTRY",
+    SEGMENT_POINT => "SEGMENT_POINT",
+    SEGMENT_FILE => "SEGMENT_POINT",
+    WORKOUT_SESSION => "WORKOUT_SESSION",
+    WATCHFACE_SETTINGS => "WATCHFACE_SETTINGS",
+    GPS_METADATA => "GPS_METADATA",
+    CAMERA_EVENT => "CAMERA_EVENT",
+    TIMESTAMP_CORRELATION => "TIMESTAMP_CORRELATION",
+    GYROSCOPE_DATA => "GYROSCOPE_DATA",
+    ACCELEROMETER_DATA => "ACCELEROMETER_DATA",
+    THREE_D_SENSOR_CALIBRATION => "THREE_D_SENSOR_CALIBRATION",
+    VIDEO_FRAME => "VIDEO_FRAME",
+    OBDII_DATA => "OBDII_DATA",
+    NMEA_SENTENCE => "NMEA_SENTENCE",
+    AVIATION_ATTITUDE => "AVIATION_ATTITUDE",
+    VIDEO => "VIDEO",
+    VIDEO_TITLE => "VIDEO_TITLE",
+    VIDEO_DESCRIPTION => "VIDEO_DESCRIPTION",
+    VIDEO_CLIP => "VIDEO_CLIP",
+    OHR_SETTINGS => "OHR_SETTINGS",
+    EXD_SCREEN_CONFIGURATION => "EXD_SCREEN_CONFIGURATION",
+    EXD_DATA_FIELD_CONFIGURATION => "EXD_DATA_FIELD_CONFIGURATION",
+    EXD_DATA_CONCEPT_CONFIGURATION => "EXD_DATA_CONCEPT_CONFIGURATION",
+    FIELD_DESCRIPTION => "FIELD_DESCRIPTION",
+    DEVELOPER_DATA_ID => "DEVELOPER_DATA_ID",
+    MAGNETOMETER_DATA => "MAGNETOMETER_DATA",
+    BAROMETER_DATA => "BAROMETER_DATA",
+    ONE_D_SENSOR_CALIBRATION => "ONE_D_SENSOR_CALIBRATION",
+    TIME_IN_ZONE => "TIME_IN_ZONE",
+    SET => "SET",
+    STRESS_LEVEL => "STRESS_LEVEL",
+    DIVE_SETTINGS => "DIVE_SETTINGS",
+    DIVE_GAS => "DIVE_GAS",
+    DIVE_ALARM => "DIVE_ALARM",
+    EXERCISE_TITLE => "EXERCISE_TITLE",
+    DIVE_SUMMARY => "DIVE_SUMMARY",
+    JUMP => "JUMP",
+    SPLIT => "SPLIT",
+    CLIMB_PRO => "CLIMB_PRO",
+    TANK_UPDATE => "TANK_UPDATE",
+    TANK_SUMMARY => "TANK_SUMMARY",
+    DEVICE_AUX_BATTERY_INFO => "DEVICE_AUX_BATTERY_INFO",
+    DIVE_APNEA_ALARM => "DIVE_APNEA_ALARM",
+    INVALID => "INVALID"
+)
+
+"""
+    get_mesg_num_string(mesg_num::Integer)::Union{AbstractString,Nothing}
+
+Given the number from our data record, get a string label. Nothing if not found.
+"""
+function get_mesg_num_string(mesg_num::Integer)::Union{AbstractString,Nothing}
+    try
+        MESG_NUM_MAP[mesg_num]
+    catch e
+        if e isa KeyError
+            nothing
+        else
+            rethrow(e)
+        end
+    end
+end
+
+end
\ No newline at end of file