The NEW Chuckaway Extension Bar from Clipacore is designed to work with the "Chuckaway" Chuck Replacement System which is designed to fit onto the 1/2" 20 UNF thread of a Core Drill. The NEW "Chuckaway" Extension Bar is also compatible with the original Clipacore Drill Adapter. The "Chuckaway" Chuck Replacement System prevents issues such as the chuck becoming loose when drilling, loss of the chuck key and the chuck becoming seized up over time. It also removes the need for using an arbor.