3/8 inch Extension Drill Bit Set for Power Tools Material and durability: made from carbon steel for wear resistance and long service life. Extension and compatibility: 3/8' extension drill bit set designed for power tools. Secure design: antidropping steel ball with an automatic locking device provides secure fixation, reducing the risk of slipping or falling and increasing bearing capacity. Easy operation: suitable for screwdriver handles or electric screwdrivers with threejaw chucks to drive the sleeve. After installation, the joint can be converted into a square drive for head to install the sleeve, offering a versatile conversion tool. Practical usage scenarios: Use with a cordless screwdriver or power drill to extend reach and drive sleeves in assisted assembly tasks. After installation, convert the joint to a square drive to complete sleeve installation work. In overhead or confinedspace tasks, rely on the autolock and higher bearing capacity to prevent slipping and ensure steady operation.