That tartan is the Little of Morton Rig tartan, No. 2349 in the ITI. It was designed in 1991 by Dr. J. C. Little of Morton Rigg, Dumfreis for the (then) newly formed Clan Little Society. It incorporates elements of both the Wallace and the Shepherd tartans.

It's not commonly seen, but seeing as the designer lives in Dumfries, and P1M is in Dumfries.....

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