The jackets use the European jacket sizes complemented by the Turkish length code, where a larger number means a longer jacket/sleeves. The EU jacket size is the recommended chest circumference divided by two in centimeters. In the chart below, you will see the average chest circumference and sleeve length of the jackets. Note that you need to add c. 20 cm (8") to the chest to get a jacket that doesn't feel like a cotton condom. There can be some variation depending on how these have been washed and how accurate the Turkish factories have been.
Size Chest Sleeve length
50-4 120 cm (47") 60 cm (23.5")
50-5 120 cm (47") 62 cm (24.5")
50-6 120 cm (47") 64 cm (25")
50-7 120 cm (47") 66 cm (26")
52-4 124 cm (49") 60 cm (23.5")
52-5 124 cm (49") 62 cm (24.5")
52-6 124 cm (49") 64 cm (25")
52-7 124 cm (49") 66 cm (26")
54-4 128 cm (50.5") 60 cm (23.5")
54-5 128 cm (50.5") 62 cm (24.5")
54-6 128 cm (50.5") 64 cm (25")
54-7 128 cm (50.5") 66 cm (26")
56-4 132 cm (52") 60 cm (23.5")
56-5 132 cm (52") 62 cm (24.5")
56-6 132 cm (52") 64 cm (25")
56-7 132 cm (52") 66 cm (26")
58-4 136 cm (53.5") 60 cm (23.5")
58-5 136 cm (53.5") 62 cm (24.5")
58-6 136 cm (53.5") 64 cm (25")
58-7 136 cm (53.5") 66 cm (26")
60-4 140 cm (55") 60 cm (23.5")
60-5 140 cm (55") 62 cm (24.5")
60-6 140 cm (55") 64 cm (25")
60-7 140 cm (55") 66 cm (26")