Shot traps are locations on the exterior of an armored vehicle where impacting shells are deflected to a weaker or vulnerable point in the armor, or simply guided to hit the vehicle, instead of bouncing or skimming off. Shot traps are undesirable features in armored vehicle design. However, modern armour piercing rounds have very little tendency to be deflected, so shot traps are no longer a major concern of armoured vehicle design.[citation needed]