The DuraPost composite gravel boards are 150mm (~6") high and are designed to be stacked to create a standard 12" (300mm) gravel board or alternatively can create a full size maintenance free fence panel. Each board is significantly lighter than its concrete alternative weighing in at only 3.4kg!

Key benefits include: 

Lightweight
Weighing in at 3.4kg compared to up to 30kg for the concrete equivalent.
 
Durable
Will not rot, warp or crack like wood or concrete 

Three Colours
High UV stability to preserve the colour 

Space Saving
Can be stacked when being transported or stored