Sizing of Alpha Military Jackets is an inexact science.
https://shop.vtarmynavy.com/alpha-industries-outerwear-c415.aspx. While we encourage people to generally order up one size it really depends on the build of the individual as to the fit and sizing. Alpha has given us the following sizing guidance (which is about 2" smaller than the norm)
Small (34-36); Medium (38-40); Large (40-42); Extra
Large (44-46); 2Extra Large (46-48); 3Extra Large (48-50)
Having said that if you are big through the chest we still recommend going up on size.
The exception is the field jacket see https://shop.vtarmynavy.com/alpha-m-65-field-jacket-p2561.aspx
which runs about a size large and have the following sizes listed X-Small (29-33); Small (33-37); Medium (37-41); Large (41-45); X-Large (45-49); 2XL (49-53); 3XL (53-57); 4XL (57-61); 5XL (61-65)
For height guidance the rough rule of thumb is that regular lengths will fit most people 5 foot 6 inches to 6 foot and Tall or Long should fit someone 6 foot to 6 foot 3 inches but there are no guarantees.
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