http://www.ebay.com/itm/281123614037

This vintage swimsuit was made in the late 1930s by Jantzen. It is made of blue knit wool, with piped side seams, a flapped coin pocket, and a white belt. They feature a false fly front, and a brief cut. The belt has a nautical-themed anchor buckle. The trunks are lined in the front, what period ads refer to as a “built in supporter”. These were sold by the Marshall Field & Company store for men. There are period repairs on the rear, one below and to the left of the belt adjuster, one by the right leg hole, and one near the center of the seat. There is a moth hole to the left of the pocket flap by the piping, a nip to the left of the false fly, several small nips in the back.

Waist (unstretched): 15″ (doubled = 30″)
Waist (stretched): 19″ (doubled = 38″)
Side Seam: 10-1/2″
Rise: 14″