Does your European Clip-on Chuck leak no matter how hard you press it down? If your chuck is a year old or older you may need a new o-ring. With age, the o-ring gets hard or develops cracks just from age. A rebuild will make it work like new again.
O-Ring, Rubber Seal, and Brass Piece inside of chuck. Used for CHK-4004 and CHK-4006
This item ships to the lower 48 for free when bought alone.