These barricades are built from heavy duty 16 gauge steel and are powder coated for long-term weather resistance. Frames are made from 1.5 38mm diameter steel tubing, while uprights are made from 1/2 steel tubing. 21 closely space uprights are used for maximum rigidity and these are fully inserted into the frame before welding, providing extraordinary strength. This model features bridge feet bases for use on smooth surfaces such as tarmac and where pedestrian traffic demands the minimum trip hazard. The barricades interlock using the industry standard hook and half-loop fastening system.