B.D.U. Pants:
Pants, Waist size in inches:
XSmall(23-27), Small(27-31), Medium(31-35), Large(35-39),
XLarge(39-43), 2XL(43-47), 3XL(47-51), 4XL(51-55), 5XL(55-59)

Flightsuits:
Chest size in inches:
Small(33-37), Medium(37-41), Large(41-45), XLarge(45-49),
2XL(49-53), 3XL(53-57), 4XL(57-61), 5XL(61-65)

Coveralls, Overalls:
Chest size in inches:
Small(33-37), Medium(37-41), Large(41-44), XLarge(44-47),
2XL(47-50), 3XL(50-52), 4XL(52-54)

T-Shirts:
Chest size in inches:
XSmall(31-33), Small(34-36), Medium(37-39), Large(40-42),
XLarge(43-45), 2XL(46-48), 3XL(49-51), 4XL(52-54), 5XL(55-57)

Hats, Caps:
Head size in inches:
XSmall(Hat size 6 3/4, Head size 21 1/8"), Small(Hat size 7, Head size 21 7/8")
Medium(Hat size 7 1/4, Head size 22 5/8"), Large(Hat size 7 1/2, Head size 23 1/2)
XLarge(Hat size 7 3/4, Head size 24 3/8").

M-65 Field Jackets:
Chest size in inches:
Small(33-37), Medium(37-41), Large(41-45),
XLarge(45-49), 2XL(49-53), 3XL(53-57)