This vintage Rolex Advertisement from Skin Diver Magazine came out in January of 1972. It reads "Next time somebody tells you they have an amazing, new waterproof watch...Tell them about the crushed Oyster."
The add reads:
"We dropped a standard Rolex Oyster case into a pressure tank.
Then we took the pressure down to 1,000 feet to see what happened.
Then we went down to 1,500 feet. And nothing happened.
At 1,700 feet the crystal began to bend a little bit.
And at 1,900 feet the back showed signs of bending.
At 2,000 feet the crystal and the back bent severely.
And if their had been a movement inside it would have been crushed. But it wouldn't have been wet. The Oyster case was still watertight. Rolex Date Submariner $285 18kt gold $1,400."