Espey is a small, vertically integrated OEM that designs and manufactures custom power electronics products for military and harsh industrial applications. Core products include power supplies, power converters, transformers, filters, and power distribution equipment, used in applications such as shipboard radar, airborne power systems, ground-based radar, and locomotives. Espey operates almost entirely as a custom manufacturer — products are engineered to customer specifications and produced in-house across the full manufacturing process, from component winding and circuit board assembly to metal fabrication and environmental testing. Customers are primarily U.S. defense prime contractors and the DoD, with smaller contributions from foreign governments and industrial customers, notably in rail. Espey's business model has two phases: funded design and development contracts, where Espey engineers a product to spec at customer expense, followed by multi-year production contracts to manufacture qualified units. The design phase is the critical competitive moment — winning a design contract typically locks Espey in as the incumbent manufacturer, creating meaningful switching costs for defense customers who face costly requalification. Espey also pursues "build to print" contracts where customers supply the design and Espey handles manufacturing. Backlog is the key forward indicator, and Espey's backlog grew from $97.2M to $139.7M between FY2024 and FY2025. Espey is a small company with roughly $44M in annual revenue and 152 employees, operating from a single facility in Saratoga Springs, New York. Customer concentration is notable — the top six customers accounted for roughly 74% of FY2025 sales.