Why do Russians Submarines Have Windows? #shorts

Why is it that Russians have windows on the sail of some of their submarines? and the reason those windows don't crack under extreme water pressures, is #NotWhatYouThink #NWYT #shorts

Music:
Solve It - Max Anson

Footage:
Russian Ministry of Defense
US Department of Defense

Note: "The appearance of U.S. Department of Defense (DoD) visual information does not imply or constitute DoD endorsement."

not what you thinkRussian NavyUS Military