Dragstrip Clothing Mens Speed Shop Biker Jacket Dragstrip Mens Greaser Hot rod Jacket in OFF-White ink. Lined Red Kap jacket , great quality jacket available in sizes Small to XX-Large. 

These are Red Kaps american work wear so they are a bit larger then UK sizes.
Jacket lying flat stretched out measure armpit to armpit is:

S 21"  ( chest 42")   ( recommended fit 38-42" chest )
M 24" ( chest 48") ( recommended fit 42- 48" chest)
L 26" ( chest 52")  ( recommended fit 48-52" chest)
XL 28" (chest 56")  (recommended fit 52-56" chest
XXL 30" (chest 60") ( recommended fit 56-60" + chest)

Thing is they are cut in a way that we recommend going 1 smaller