#20: WD-40
Squeaky doors were not the assignment. In 1953, a small San Diego company called Rocket Chemical set out to develop a formula that could prevent rust and displace water for aerospace applications. The team finally succeeded on its 40th attempt, which explains the name: WD for Water Displacement, 40 for the successful formulation number. The product soon escaped its specialized industrial setting and found a far larger audience among mechanics, homeowners, hobbyists, and anyone fighting a stubborn bolt.
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