I think CanberraR3's idea of getting rid of the box around the triangle is an excellent one as it would really clean up the look of the shirt. There is a colourful union jack in the background anyway which would stand out even more - no real need for 2 superimposed on one another. But I still like the design on the back
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If Hanso's idea of a 2 x 2 inch chrome ring on the front is adopted - then the full design with the triangle + box would appear at least on the front of the shirt.