CFA AdaptersContinuous Flight Auger Adapters Adapters to suit auger drive units and earth drills to adapt from the drive hub to the hex drive of the CFA. SIzes available include: 50. 8mm Round to 1 1 8" Hex 50. 8mm Hex to 1 1 8" Hex 65mm Round to 1 1 8" Hex and 50. 8mm Round to 1 3 4" Hex 50. 8mm Hex to 1 3 4" Hex 65mm Round to 1 3 4" Hex 75mm Square to 1 3 4" Hex All CFA adapters come with a pin and clip to attach to the auger drive.