36s is Slim 36r is Regular. Slim is extremely Slim, my son is 6'2" @ 110lbs, the Slim fit is perfect for him.
What size pants come with a suit?
When you buy a suit off the rack, you're buying a suit with a “standard drop”—the difference between the chest size of your jacket minus the waist size of your pant. The standard drop is 6, which means if you wear a size 38 jacket, the pants will be a size 32 waist (38 – 32 = 6).
What suit size is 40?
Internat. Suit Size US Suit Size Chest (Inch)
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S 36 36
M 38 38
M 40 40
L 42 42
Suit and sport coat sizes have one number and one letter (for example, 38S, 40R, 42L). The number is your chest measurement and the letter refers to the jacket's length ' short, regular or long.
All chest sizes come in three length: R(Regular), L(Long) and S(Short). An easy way to explain the difference between "Regular", "Long" and "Short" is, for "Short", both the sleeves and length of the overall jacket will be 1" - 1.5" shorter than "Regular", and same applies to "Regular" vs "Long". 36 SHORT.