Companies are even implementing high-tech research techniques using mini-spy cameras and one-way mirrors to study how razors cut and even the styles people use to shave.

• 从原始的石器时代到现代的剃须刀刀片奇迹，这个日常的事情：带领观众到幕后行业，剃须甚至可以追溯到伟大的埃及法老。