S is for small, 127 is the number of the button. This button is 5/8″ and is good for vests, light jackets and sleeve buttons.
The material is Britannia pewter. There are 5 buttons flat face buttons this in different sizes, also a tiny button for shirt collars.
Good for your vests, light jackets and shirt cuffs. Generic.
Matching buttons, 129, 130,128,126 and 147 in descending sizes.