The FOS420 light source can be used with premise and campus cabling networks that utilize multimode fiber, or Singlemode fiber under 5km. The ST connector outputs can be adapted to any cable plant with hybrid adapters or hybrid cables. The FOS420 becomes a powerful low cost troubleshooting and maintenance tool when used with an Advanced Fiber Solutions FOM120 or FOM220 power meter. Lightweight ,ergonomic design is great for field use. Order online today!