Yellow Powder Coated Bolt Down Bollards easily mount to any surface which eliminates the need for core drilling and excavation. They're manufactured with Schedule 40 Steel and feature a welded-on cap. Once installed, these bolt down bollards provide instant protection against damage to things such as utilities, meters, electrical boxes, dock doors and more. Product dimensions for 4" O.D. (36" or 42" high): 8" x 8" base plate, 1/2" thick, with (4) 3/4" corner holes. Product dimensions for 6" O.D. (42" high): 10" x 12" base plate, 1/2" thick, with (4) 3/4" corner holes.