The LFS-4000 is an optical fiber processing tool designed to splice standard, large-diameter and specialty fibers. 2 An Introduction to GPX Glass Processors and LFS Large Fiber Splicers Thorlabs' Vytran® Filament Fusion Splicers for Standard, Large-Diameter, and Specialty Optical Fiber or Soft Glass Fiber combine filament fusion technology, a high degree of user process control, and simple operation. It's an ideal option. Fusion splicers are essential for creating low-loss, high-performance fiber optic connections in telecom, FTTH, and data center applications. Top-rated models. AC/DC Adaptor, input: AC100-240V, output: DC13. Li-ion battery Working altitude: 0-5000m.