This 8 X 12 X 12 Manhole Box Trench Box provides the needed inside clear span, while reducing the amount of excavation and restoration required. Standard models include two walls and two spreader assemblies with a pipe clearance of 45″. All trench boxes are certified by a professional engineer to meet OSHA standards. Dimensions for trench box are 4’ X 12’ X 12’. Allows for pipe clearance of 45’’. It is important to wear a hard hat and carry your training card while using this model.