WSM N2205 k rail road barrier set of 8, N scale
These are you basic concrete construction barriers.
These are the most detailed that you can get in N-Scale
They even have the loop and pin connections, along with lifting eys, bridge rail slots, fork lift slots, perfect scale.
The set comes with the (2) standard sizes.
4-12ft and 4-20ft barriers – always includes size variety on your layout to add interest!