The Hilti DD-SA 77 3” Starting Aid Part # 2069669 Core Drill Centering Guide is a specialized tool designed for core drilling tasks. This product, specifically made by Hilti, is a model designed for accurate and precise drilling. The 3” starting aid provides additional support and stability during the drilling process, ensuring a reliable and efficient operation. Perfect for professionals in the construction and drilling industry, this core drill centering guide is a valuable tool for achieving consistent and high-quality results.