The jacket, an EXO Skelton compression shirt that is a custom version of the ones Unequal sells to public consumers, has two rib protectors on either side.
For much of the 20th century, it was custom for Ivy League graduates (and their imitators) to keep at least one "odd jacket" in their wardrobes to wear with khakis, gray flannels or wide-wale corduroys, rather than slim cargo pants, purple chinos or the "winter whites" that are now a trend in Italy.