Precise and efficient operation Once the stop ring is attached to the drill, it does not shift. This enables drilling multiple holes quickly and easily to a consistent, precise depth. Eliminates the need to wrap tape around drill bits to control depth, saving time and improving accuracy. Helps prevent repeated deep drilling or under depth issues. Durable material and protection Made of carbon steel for durability. Blackened with antirust oil to enhance rust protection. Safe to use and the screw collar does not damage the drill. Drill stop bit collar set 8 stop collar sizes: 1/8, 1/4, 7/32, 1/4, 5/16, 3/8, 7/16, 1/2 for the most common drill sizes. Suitable for twist drill or tip drill or type of bit. Use scenarios Woodworking and cabinetry: set a fixed depth for shelf pin holes to ensure uniform placement and stable shelves. Furniture assembly: drill pilot holes with consistent depth for screws or dowels, reducing the chance of throughdrilling or breakage. DIY projects requiring repeatable depths: create multiple identical holes in panels, frames, or hobby projects with minimal setup. Compatibility and performance Designed to fit standard drill bits and provide repeatable depth control across a range of common sizes. Helps improve drilling consistency in both professional and home workshop settings.