>>509497377
>KE
According to an article published by Andrei Tarasenko, the first version of the T-72B hull armour (referring to the "Improved T-72A" from 1984) was 20% more effective than a homogeneous plate by mass, so the ME coefficient is 1.2. In a separate article, the armour is stated to have an effective thickness of 490mm RHA.
>HEAT
Applying the ME coefficient of 1.2, the "Reflection-1" armour would have an effective thickness of 496mm RHA, which makes it essentially equivalent to the 500mm RHA effective thickness of the basic T-72A

And in modern battlefield HEAT is a far more common tank threat that KE.