Collet Insert (CI) for Capacitor Discharge (CD) Studs
Ideal when you want an exact depth inside the collet without having to use stops.
The gun setup usually requires an adaptor to fit the gun, typically either a B-CI adaptor or Soyer/Euro-CI adaptor.
The first number is the stud diameter and the second number is the depth the stud will go inside the collet.
Many other sizes are available via special order. Call for more information and pricing.