Electric Shavers
What shaves properly?
"The holly Torah explicitly forbids to shave beard with  blade or razor"
However, 
80 years ago, rabbis at the time allowed the use an electric shaver
Because in the old shavers the blade below the foil does not touch the face skin directly because the foil 
was thick and dense.
The bristles penetrates into the thick foil and the blade rotates quickly
under the foil and cut the bristle like 
scissors
It was a good solution which was used for a long time,
but it had not been tested over the years !
At the same time leading manufacturers of electric shavers :
 "Philips" "Brown" "Remington", "Panasonic", etc.

Improved more and more the foils of the electric shavers, so the resolt of shaving with electric shaver became very close the 
feeling smooth almost like shave with a razor 
Advances and new developments have created a problem to traditionally observant according to the holly Torah.
All manufacturers of Shaver published the improvements that make the foil
more and more thin they
 declare that their foils allows shaving reusolt
smoother and better than before
Twelve years ago rabbis from Rabbi Gross's court, together with an expert in shaving and a senior engineer, began to examine and investigate all the shavers in the market and found that all of them had a real fear of corrupting like a razor the bristles on the face.