Model is 5' 10"/ 178cm and 174lbs/ 79kg. He wears a size 40. Please use this info as a general guide as measurements are approximate. Size Shoulder Chest 36 18.9" / 48cm 41.3" / 105cm 38 19.7" / 50cm 43.3" / 110cm 40 20.5" / 52cm 45.3" / 115cm 42 21.1" / 53.5cm 47.2" / 120cm 44 21.7" / 55cm 49.2" / 125cm Size Length Sleeve 36 24" / 61cm 22.8" / 58cm 38 24.6" / 62.5cm 23.2" / 59cm 40 25.6" / 65cm 23.8" / 60.5cm 42 26.2" / 66.5cm 24.4" / 62cm 44 26.8" / 68cm 24.8" / 63cm In order to best determine fit, it may be helpful to compare our garment’s measurements to a similar garment you already own. Lay your garment on a flat surface and take all measurements from the outside of the garment. Click here to check out our Garment Measuring Guide. ** If you are still confused, you can Contact Us to help you choose the size. **