👷Extends any Forstner bit shank an additional 5-3/4 inches, Helps you use standard forstner drill bits drilling for flat bottom holes or start deep hole turning projects like on larger vases or containers;
👷The collet inside diameter is 3/8 inch(9.7mm). This tolerance is very tight and designed to accept forstner bits with shank sizes of 3/8 inch or slightly smaller;
👷High-carbon steel construction, precision ground and polished, ensuring it's sturdy and durable;
👷Two set screws and hex key included. To fasten the shank in place, use the hex key to tighten these screws;