The Non conductible bollards (150mm Round) are ideal for protecting power generators, power boxes or any electrical unit that has an earth circuit running around it. Non-Conductible bollards are made of heavy 15mm wall plastic and can be installed 500mm deep in a concrete footing, leaving 1 metre above ground. There are four holes in the in-ground section for concrete tie bars for added strength. Colours are Blue or Yellow plastic with a rounded dome top. Also available in Black (Standard)