The Z4 - 4-jaw chuck kit is the perfect wood lathe accessory for turning bowls, platters, spindles and decorative pieces. The 4-jaw self-centering chuck is CNC precision-made from high tensile steel with a geared jaw system for easy operation and excellent project holding power. Improved design of the chuck sliders gives added strength for attaching a variety of available jaw set accessories. This Z4 chuck might require your choice of appropriately sized threaded insert adapter to be installed into the rear of the chuck to mount the chuck on your lathe. Meticulously machined chuck body and internal gearing system operates flawlessly for reliable closing and opening operation with the included special chuck key. The Z4 chuck isrobust and has a larger chuck diameter which is ideal for use on larger lathes. Use Z4 to hold small bowl or other lightweight projects for turning. Sharp threads cut into wood for best holding power. Requires a pilot hole bored in the wood before installation. Might have to purchase separately and use either of the following inserts. 70-120 for (M33x3.5 ISO RH lathe spindles); 70-121 has (1 inchesx8TPI UNC RH threads); 70-122 has (1-1/4 inchesx8TPI UNS RH threads) and 71-123 has (M30x3.5 RH threads.)