These bollards has a powder coated finish and is applicable for either indoor or outdoor use. It can provide protection in work areas or personnel. The plastic caps can be removed on ,1-3/4", 4-1/2" and 5-1/2" diameter units and bollard can be filled with concrete. Steel caps are welded on the 6-5/8, 8-5/8" diameter units. The base plate has four (4) pre-drilled mounting holes for easier installation. Baked in powder coat finish for added toughness.