Filled with non-newtonian fluid, these speed bumps behave like a fluid when a car is under the speed limit. If the vehicle exceeds the speed limit, the fluid hardens and become a speed bump

\[source, video: buff.ly/2xIDxOX (https://buff.ly/2xIDxOX)\]

https://nitter.moomoo.me/Rainmaker1973/status/1645378900309028864#m