Sep 14, 2020 · You might have heard of these, they are also known as “cross-recess”, “cross-head”, or “cross-point”. How did they come to be, and what is the main problem with them? A man named John P. Thompson invented (and patented under US Pat. No. #1,908,080) “recessed cruciform screw” in 1932. In 1933 he also patent-protected a matching ...
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