Model 222 Wedge Type Quick Change Tool Post Set This Model 222 Quick Change Tool Post Set: Essential set is supplied with: 1 x Model 222 Wedge Type Tool Post 2 x Model 200 Standard Tool Holder 1 x Model 200 Tool Holder with V- Groove Delux set is supplied complete with: 1 x Model 222 Wedge Type Tool Post 2 x Model 200 Standard Tool Holder 1 x Model 200 Tool Holder with V- Groove 1 x Model 200 Boring Tool Holder 1 x Model 200 Parting Tool Holder - Angled 1 x Model 200 Knurling Tool Holder The Model 222 quick change tool post is a wedge type tool post system for lathes with 250-380mm /10-15" swing.The tool post and tool holders are of hardened steel construction for excellent rigidity and the mating faces are ground for better repeatability when changing tools. Specifications for the Tool Post: The Model 222 Quick Change Tool Post is a wedge type quick change tool post system that uses sliding wedges in the dovetails of the tool post to clamp tightly on the tool holder dovetail. This cut-away view shows how the sliding wedges have teeth which engage in the thread of triple start screw operated by the locking lever. A: 3"B: 4.3/4"C: 2.3/4"D: ø5/8" Dia., 5/8"x18TPI Thread Specifications for the Standard Tool Holder: This tool holder is designed to hold square tools up to 16mm.A: 44.5mmB: 16.5mmC: 12.5mmD: 28.5mm Specifications for the V-Groove Tool Holder: This tool holder is designed to hold square tools up to 16mm and round tools diameter up to 13mm.A: 44.5mmB: 16.5mmC: 12.5mmD: 28.5mm Specifications for the Boring Tool Holder: This boring tool holder is designed to hold ø19mm round tools using the split sleeve (included) and ø25mm without the sleeve.A: 44.5mmB: 22mmC: ø19mm with sleeve, ø25mm without sleeve Specifications for the Parting Tool Holder (Angled): This parting tool holder will hold parting blade up to 3/16"x5/8". A: 1.3/4"B: 5/8"C: 3/16" Suitable Blades:HSS Parting-off Blade 3/32"x5/8" x5" Specifications for the Knurling Tool Holder: A: 44.5mmB: 16.25mmC: 12.5mmD: 13mmE: 19mmF: 68.5mm