3.5mm replacement bit for 492523 3.5mm adustable countersink drill bit with a free spinning depth stop. The Centrotec shank can be used with all three-jaw chucks for no-slip performance or in conjunction with Festool's Centrotec chuck system. With the Centrotec design there is a better transfer of force with no chance for bit slippage or marring of the drill bit. Reduce the weight of the drill by nearly ½ pound and the length by nearly 1-1/2” with the Centrotec system. Additionally the Centrotec system offers a quicker way of changing bits than a keyless chuck with less run out. Economically packaged in 5 piece pack.