The European standards

EN 1522 / EN 1063 specified 7 levels of protection: 
B6 protection class - B7 VPAM 7 - became VPAM 9.
B2 can withstand a 9 mm,. 38 of special and lesser rounds what will lead to slowing down bullets from weapons of large guns.
B3 can withstand .357 Magnum rounds or lesser threats
B4 can withstand a.44 Magnum rounds or lesser threats. Good for small hand grenades blast.
B5 is capable of withstanding a .357 Magnum at 5 meters and B6 7.62 x 39 rounds from Kalashnikov rifle.
B6 which is a relatively high level of security and above the armour is designed to stop some serious threats such as gun fire ranging from 7.62х51 (.308) up to 30.06 AP (Armour Piercing) and Penetration rounds.
Some cars (BMW X-5 Series, Audi 90) are rated at B4 or B5 protection level which can provide adequate protection against certain threats.Very covert, low key no visual difference between normal "Soft skin" vehicles 
Security vehicles such as (Range Rover, BMW, Toyota, Mercedes) B5 B6 or B7, level of protection – Extra weight more powerful engines They are very resistant to explosions IED Hostile enviroment

How does bullet proof glass work
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​At first glance, bullet-resistant glass looks identical to an ordinary pane of glass, but that's where the similarities end. An ordinary piece of glass shatters when struck by a single bullet. Bullet resistant glass is designed to withstand one or several rounds of bullets depending on the thickness of the glass and the weapon being fired at it. So, what gives bullet-resistant glass the ability to stop bullets?
Different manufacturers make different variations of bullet-resistant glass, but it is basically made by layering a polycarbonate material between pieces of ordinary in a process called lamination. This process creates a glass-like material that is thicker than normal glass. Polycarbonate is a tough transparent plastic -- often known by the brand name Lexan, Tuffak or Cyrolon. Bullet-resistant glass is between 7 millimeters and 75 millimeters in thickness. A bullet fired at a sheet of bullet-resistant glass will pierce the outside layer of the glass, but the layered polycarbonate-glass material is able to absorb the bullet's energy and stop it before it exits the final layer.

IED Attack

The vehicle below fell victim to an IED/roadside bomb attack in Iraq. Despite the appearance of massive external damage, there was absolutely no penetration to the passenger compartment—all six passengers survived and walked away. While we don't certify our vehicles against IED attacks, this vehicle is an example of the real-life protection that armouredcars4x4 , Armored vehicles can provide.

Bomb blast IED lives saved again Yemen

F350 protected in accordance to Euro Norm B7 ballistic level withstood the attack in Yemen. No casualties.

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