8-Piece Drill Depth Stop Ring Set (3-16mm) with Hex KeyProduct Features & DetailsWide Size Range: This kit includes 8 standard drill depth stops in various sizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm and 16mm, perfectly compatible with drill bits of different diameters to meet diverse drilling needs.Premium High Carbon Steel Construction: Crafted from Good-quality durable carbon steel with a blackened surface finish, these depth stoppers offer excellent rust and corrosion resistance, high hardness, and exceptional wear resistance — they are not easy to deform or harm even with long-term heavy use.Precise Depth Control: The drill bit depth stopper is mainly designed to fix the maximum drilling depth on the drill bit, enabling accurate and consistent depth control for every hole, ensuring uniform hole depth for professional and precise drilling work. It is also highly convenient for round wooden mortise drilling tasks.Easy to Operate: This depth control kit is simple and quick to use, even for beginners.Step-by-Step Usage:Measure the target drilling depthSelect the corresponding specification depth stop ringLoosen the clamping screw on the stop ringSlide the ring onto the drill bit and adjust to the marked depthTighten the screw firmly with the included hex key to secure itThe included Allen key (hex wrench) makes adjustment, installation and removal of the depth limiter fast and hassle-free.SpecificationsMaterial: Good-quality carbon steelSurface Finish: BlackenedSizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, 16mmPackage Includes: 8 x drill depth stop rings, 1 x hex wrench