As a means for CO 2 laser beam, the handpiece for articulated arms was consisted of couple, fiber connecter, flexible metallic tube, lens.

In the metallic tube producing method, a maximum diameter of the plug or tapered mandrel bar may be larger than an outside diameter of the mother tube.

When electric insulation is required, non-metallic coating, protective non-metallic tube or insulating joint, etc., can be adopted for the insulation implementation.