This is a set of two Fluke Networks DTX-SFM2 SM Fiber Modules for DTX 1200 DTX-1800 DTX SFM2. They are compatible with F-Type Coaxial, RJ11, and RJ45 cables. The brand of this unit is Fluke and it was made in the United States. These modules are suitable for business and industrial use, and fall under the category of cable testers and trackers.