Texas First Trench Safety Slide Rail Shoring by TWF is a modular component system that utilizes a “dig-and-push” method that greatly reduces the risk of cave-ins and trench collapses associated with open trench excavations. One benefit is that this increases safety for adjacent structures and for your personnel. With TWF’s variety of modular components, the system can be utilized in a wide range of applications to include unique designs of two-, three-, or four-sided pits with clear open span.