Green’s Dictionary of Slang

draught-board suit n.

a dinner jacket.

[UK]Dly Gaz. for Middlesborough 2 Feb. 3/4: There is no doubt that a Bishop could go to heaven, even in a fifty-shilling draught-board pattern suit!
[UK]Derbyshire Times 7 Jan. 7/2: Following him came [...] Mr William Chewkle in a brand new ‘draught-board’ suit.
M. Pemberton Gold Wolf 122: He even sends a man in a draught-board suit to ask after my health.
[UK]E. Pugh City Of The World 272: There’s plenty o’ fences [...] as ’ll fit you up wi’ what you want, all proper, from spats to a draught-board suit and bag-cap to match.
W. Saint-Mande Halcyon Days in Africa 44: A smart young man, in a draught-board suit, came on with a beautiful girl, scantily dressed.