Headstock thread adaptor for 1" x 12tpi Lathes.
Optional chuck insert for using Viper3, Viper5 or Nexus3 chucks on a lathe with a 1" x 12tpi thread on the headstock.
The internal thread is 1" x 12tpi and the external thread is M33 x 3.5. Both threads are 32mm in length.
Compatible wih the following models (among others):