NATO targets

NATO targets are a series of standard armoured targets defined by NATO designed to test the armour penetration of weapons. The purpose of the triple heavy target is to represent the difficulty a projectile would face in penetrating the skirt, roadwheel, and hull of a Soviet tank.^[1]

They are defined as:

Target type	Angle of target ^[clarification needed]	First plate thickness	First plate hardness	First air gap	Second plate thickness	Second plate hardness	Second air gap	Third plate thickness	Third plate hardness
Single medium	60°	130 mm
Single heavy	60°	150 mm	260-300 kp/mm^2
Double medium	60°	40 mm		150 mm	90 mm
Double heavy	60°	40 mm	308-353 kp/mm^2	150 mm	110 mm	260-300 kp/mm^2
Triple medium	65°	10 mm		330 mm	25 mm		330 mm	60 mm
Triple heavy	65°	10 mm	412-438 kp/mm^2	330 mm	25 mm	100-122 kp/mm^2	330 mm	80 mm	308-353 kp/mm^2

References

1. Kelley, Orr (1989). King of the Killing Zone. p. 176. ISBN 0-393-02648-5.