[Material] Drill Stop Collar Made Of High Quality Carbon Steel, Durable And Reusable, Will Be Firmly Fixed Where You Put It, And Not Easy To Slip, Damage The Drill. Assorted Sizes: 3Mm, 4Mm, 5Mm, 6Mm, 8Mm, 10Mm, 12Mm, 16Mm. Comes With 1 Set Of Drill Bit Limiter Rings (8 Pieces In Total) With 1 Allen Key.[Easy To Use] Just Select The Appropriate Depth Stop Bit, Slide The Stopper On The Drill , Set The Required Depth With A Ruler And Then Tighten. Do Not Spin The Drill At High Speed, It Is Out Of Balance.Drilling Depth Control: Use The Adjustable Dct Screw Locking Collar With 8-Piece Drill Split Ring To Precisely Control The Drilling Depth. A Hole You Drill; Great For Depth Drilling When Precise Measurement Is Needed For Hole Depth; Designed To Hold Your Drill Bit In Place And Grip The Entire Diameter Of Your Drill Bit Without The Screw Ever Touching The Shank.[Wide Applications] The Drill Depth Stop Set Is Used As A Mechanical Collar, Perfect For Precise Drilling, Which Is Suitable For Production And Repeated Drilling Work, Suitable For Drilling Wood Or Walls.-8