Rather than carrying three different sized grouser bars, we’ve designed a two piece unit that can extend and collapse to fit three different spans. Use this product to stabilize the bottom of a rolling tower. Fits diagonally from one side to the directly opposite or diagonal side. Bar fits around the vertical scaffold frame tube and a slider bar slides towards the end locking the bar to the scaffold frame. Slider bolt can further be tightened locking the bar in place. Most competing models are not able to be adjusted or tightened. Slider and hardware are galvanized and bar is powder coated hi-visibility yellow.