Shopping gives u a different life.Features:100% brand new and high quality.High hardness， non-slip， large torque， long life and durable.The screwdriver head has strong magnetic so that it can self-lock the connecting rod.Strong practicability， it can change external six angle into internal six angle.It can join electric screwdriver， screwdriver， screwdriver nozzle， screwdriver head.It applicable for exchanging the sleeve and the joint， prolonging the connecting rod.It can be flexibly used in situation of narrow space， use it to reach the work-place where hands can not reach.Specifications:Material: CR-VShank shape: Hex shankShank diameter: 1/4 inch Total length: 75mm/100mm/150mmPackage Includes:3pcs Magnetic Drill Bit ExtensionHave a nice day.