About BAE Systems Platforms & Services BAE Systems, Inc. is the U.S. subsidiary of BAE Systems plc, an international defense, aerospace and security company which delivers a full range of products and services for air, land and naval forces, as well as advanced electronics, security, information technology solutions and customer support services. Precision measurement equipment such as calipers (both vernier and digital), height gauges, surface plates, protractors, gauge blocks/pins, micrometers, depth gauges, thread gauges, plain plugs and ring.