Abstract: A chuck is described for use with another similar chuck to hold a hollow cardboard tube on which a web, such as plastic film, is spirally wound after it has been slit into a desired width on a slitting and rewinding machine. The chuck has a plurality of sears which are positioned within specially shaped slots that are recessed in the chuck. Each sear is generally L-shaped and has a first leg for engaging the open end of the tube and a second leg for engaging and gripping the inner periphery of the tube, as the open end of the tube engages the first leg and causes it to move and rock the sear in the slot.