Search this download for XXIMC, it's described and listed there, under "Transport Corps" on page 453:
https://www.google.co.uk/url?sa=t&so...YvfMlXUMKGExhs
Badge Index – Arms & Services, AF(I), IST/ISF
SUPPLY & TRANSPORT/SERVICE
CORPS
Supply & Transport Corps 1901-23
Transport Corps
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s/t 16 Bullock Train – straight 16BT b
s/t 16 Transport Corps – straight 16TC b
s/t 19 Bullock Train – straight 19BT b
s/t 19 Mule Corps – straight 19MC b
s/t 20 Transport Corps – straight XXTC b
s/t 21 Mule Corps – straight XXIMC b
s/t 22 Mule Corps – straight XXIIMC b
but 22 Mule Corps – crown over XXII over MC (Extra
Quality) - large
KC b
s/t 23 Transport Corps – straight 23TC b
s/t 24 Pack Mule Corps – straight 24PMC b
s/t 24 Mule Corps – straight 24MC b
s/t 25 Mule Corps – straight XXVMC b
s/t 26 Transport Corps – straight 26TC b
s/t 27 Transport Corps – straight 27TC b
s/t 28 Mule Corps – straight 28MC b
s/t 29 Transport Corps – straight 29TC b
s/t 30 Mule Corps – XXX over curved MULE CORPS b
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