The IRWIN SPEEDBOR Lock-n-Load Quick Change Extension Bit Holder is built to last with a durable carbon steel sleeve for a long life. The Lock-n-Load system creates a quick, one-handed release system while the patented jaw design holds bits securely on 6-flatted shanks and well as ball detent bits. Magnetized to keep bits from becoming lost during changes, the 1/4" range also holds insert bits.