Now on eBay! LINKThis vintage men’s swimsuit was made by Sarby, probably just post-war. It differs from 1930s swimsuits pretty much only in its lack of belt loops. It is a ribbed wool material with a flapped key pocket. The front is lined and there is a drawstring waist. They are in excellent condition and don’t have any of the usual tell tale signs of wear.Waist unstretched : 14″ (doubled =28″)Waist stretched: 20″ (doubled = 40″Rise: 15″Side Seam: 11″ 
This vintage men’s bathing suit was made in the 1930s. It is navy blue wool with a waffle pattern weave. Double racing stripes down the sides, and a tunneled belt. Diamond shaped crotch gusset, d-ring buckle. The front is lined. I see one small moth bite on the back.
Waist (Unstretched): 11″ (doubled = 22″)
Waist (Stretched): 17″ (doubled =34″)
Rise: 14″
Side Seam: 14″
A general overview of men’s bathing suit styles from the 1920s through 1940s. Blue and Burgundy were the most popular colors. Almost all have belt loops, though not all currently have belts.
Now on eBay! LINK
This vintage men’s swim suit was made in the 1930s by Gatner Wikies. There are ribbed wool, and have belt loops, but no belt. There is a flapped key pocket.
Size: 34
Waist side to side (unstretched): 15″ (doubled = 30″)
Waist side to side (stretched): 18″ (doubled = 36″)
Rise: 13-1/2″
Side Seam: 10″
This vintage swim suit mas made in the 1930s through mid 1940s by Jantzen. It’s blue ribbed wool and lastex. It has a white belt with a hammered silvertone buckle. There are two small moth bites on the right hip by the waistband. There is a flapped key pocket, and the front is lined.
Marked size: 36
Waist side to side (unstretched): 15″
Waist side to side (stretched): 18″
Rise: 13″
Side Seam: 9″
Now on eBay! LINK
This vintage swimsuit was made in the 1930s. It is not marked as to a manufacturer, but does have the “Lastex” tag. There is typical wear, and a tear on the side seam at the top. They are lined in the front and have a buttoned key pocket.
Waist side to side (unstretched): 13″ (doubled =26″)
Waist side to side (stretched): 17″ (doubled = 34″)
Rise: 13″
Side Seam: 7-3/4″
A happy “go skateboarding day” to you from Vintage-Haberdashers.
1930s swim trunks sold by the R.H. Macy Company of New York. Great belt buckle. Heavy kersey-type wool, not the typical knit. Flapped key pocket. Early Talon zipper.
Now on eBay! LINK
This vintage men’s bathing suit is from the 1920s or early 1930s. No makers label, just a content label saying that it is part wool. Feels like the rest is probably cotton, because, if anything, it feels like a soft cotton knit T-shirt. It has a skirt and side cutouts. Sizing on these one pieces can be a bit tricky- please refer to the measurements.
Waist unstretched: 13″ (doubled = 26″)
Waist stretched: 20″ (doubled = 40″ )
Shoulder to crotch unstretched: 22″
Shoulder to crotch stretched: 26″
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