Welded Steel Construction: This safety bollard is made of Q235 steel features high hardness, great strength, and durability. Tube Thickness: 0.08 in/2 mm. Height: 48 in/122 cm. Welded and integral structure enables the bollard post to withstand impact. Yellow Finish 4.5' O.D: The steel pipe safety bollard is highly visible and grabs attention due to its bright yellow finish and a black stripe on the top. The powder-coated finish guards the parking bollard against oxidation, UV rays, and fading or rusting. Diameter: 4.5 in/11.4 cm. Stable Base Plate: Our traffic bollard adopts a sealed bottom design, increasing the grounding area. No need to worry about sand or cement oozing out the bottom. Base Size(L x W): 7.9 x 7.9 in/20 x 20 cm, Base Thickness: 0.2 in/5 mm. More stable and durable, not easy to deform. Easy Installation: This guardian steel bollard is easy to install with four pre-drilled mounting holes in the base. It comes with four anchor bolts and a wrench