A fixed clamp holder is used, which allows a firmer and more attachment Good rotation flexibility, it can easily rotate and adapt to different working environments to increase work efficiency The two screws on the extension rod can be tightened ensures a stable and secure attachment without loosening Suitable for milling drills, especially for Deeply hole milling and openings. Especially suitable for installation work, pipe feedthroughs and window constructions to facilitate drilling in wood Selected from stainless steel, which can withstand repeated use and demanding working conditions. It has a long service life and has vibrations and shock absorption functions to reduce vibrations on the equipment, Manufacturer: LiRRvb