Tel designs and manufactures portable avionics test equipment used by technicians to verify aircraft navigation and communication systems. Its instruments enable "ramp testing" of transponders, radios, and IFF (Identification Friend or Foe) systems to ensure they function within specifications. Tel serves two primary markets: the U.S. military and allied NATO forces, and the commercial aviation sector, including airlines and maintenance shops. Tel generates revenue from hardware sales and recurring calibration and repair services. Tel secures military business through government contracts and multi-year upgrade programs, and Tel sells to commercial customers through direct channels and distributors. The CRAFT multi-purpose test set, used by the U.S. Navy, represents a key product. Tel is also ramping production of the SDR-OMNI, a software-defined radio platform that consolidates legacy test functions into a single handheld unit. This platform is central to Tel's strategy of replacing aging equipment in the commercial market and expanding into the broader secure military communications test sector. While Tel maintains a leading position in the specialized IFF testing niche due to high certification barriers, Tel faces risks related to electronics supply chain reliability.