....damn. My whole career I've seen these things all over the world but never knew they had an actual name. Designed for anti-tank area denial AKA "tank traps" originally they can be used for all types of vehicles. I even saw small (but effective) anti-truck versions (ironically in the Czech Republic!) made from sturdy pointed sticks. I so want Forbin to toss the small metal ones out his car window and make a new commute video for our viewing pleasure! Awesome design though....no matter how they are tipped or tumbled or tossed they always land in a menacing position. And there is little area for the enemy to hide behind for cover/concealment.