Durajoint Waterstop is a PVC product designed for use in concrete construction containing joints, one side of which is subject to hydrostatic pressure. The material is gray in color. Durajoint Waterstop is used as a barrier within the joint to prevent the passage of liquid through or across the joint. It is embedded in the concrete on both sides of the joint and spans the joint. It is designed to accommodate lateral and transverse movement which can cause a joint to open, close, or misalign. Durajoint Waterstop Type 3A is a ribbed type with a centerbulb.