This type of chuck is often called a split chuck. It consists of a hollow spindle, usually threaded at one end, the forward end being accurately drilled or broached and split, and able to close on and grip the work being turned as it is tightened into the hollow driving spindle of the lathe headstock, using the draw bar or draw screw. It is mostly used for comparatively small work and sets of variously sized split chucks are available for a given lathe. Being hollow it has the advantage that it can accommodate long lengths of wire, and for this reason it is often called a 'wire chuck'.