Circa 1950s - many would simply call this a bullet bra However, this example by Hollywood Maxwell used the trademark whirlpool because of the company's proprietary spiral stitching on the cups.

Whirlpool' Spiral Stitch Overwire Bra By Hollywood Maxwell

security-scripts/hacking-secret-ciphers/dictionary.txt at master

Hop Act PT 4, PDF, Wafer (Electronics)

SpellCheck/dictionary.txt at master · sjrahimian/SpellCheck · GitHub

My daily wear vintage undergarments per request : r/VintageFashion

1950s Lingerie inspired by Hollywood Maxwell's Whirlpool Bra

suggest/resources/frequency at master · bitonic/suggest · GitHub

1950 womens Hollywood Maxwell V-ette Whirlpool strapless.bra

Final product (maybe) for my sister's 70s themed birthday party! : r/VintageFashion