The 3.5" Bollard Cover is designed to fit posts with a diameter of 4 1/16" (4.0625") and is available in two heights: 52" or 68". It comes in 10 standard colors, and if a custom length is desired, specifications can be provided at checkout. This cover is made using rotational molding, providing both strength and durability for long-term protection. Custom colors and logos can also be requested; please contact us for more information.