Corporate holdings include:
API Electronics, Inc.

Filtran Ltd.: filters, transformers, power supplies, inductors/chokes

National Hybrid Inc. 1553 data bus products, power controllers, custom hybrid microcircuits
NanoOpto.: optical components, data storage, imaging, display and communications Ampower: power transistors   
Unitrode: power transistors & darlingtons

Solid Power Corp homotaxial power transistors   
MSI Electronics: varactor tuning diodes, ASI Microsystems: custom hybrid circuits  REL Labs: standard hybrid amplifiers, oscillators
TM Systems: government systems – manufacture VRS (Vertical Reference Systems), VLA (Visual Landing Aids), SGSI (Stabilized Glide Slope Indicators)    

•Islip Transformer & Metal Co.: Government systems – Radar Threat Indicator Keytronics Inc.: power transformers, reactors, magnetic amplifiers, PS and converters