Robertson, Phillips, and the History of the Screwdriver
18:33
Where DO screws come from?
18:10
Duck(t) Tape: the World's Most Useful Tool.
56:32
Best of History Guy: Hats
9:46
How America RUINED the world's screws! (Robertson vs. Phillips)
16:06
The Greatest Mathematician Who Ever Lived
55:10
Best of The History Guy: Invention
11:07
Why are Pozidriv screws better than Phillips?
52:31