Combat Gear //

Night Vision

Modeling, Simulation, Testing and Training //

Automatic Test Equipment
Test and Evaluation

Professional Services and Consulting //

Foreign Military Sales

Research and Development //


Small Business Classifications //

Small Business

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Seiler Instrument manufactures, assembles, and tests precision optical instruments and components for military and commercial use. We are the Original Equipment Manufacturer of the optical fire control systems used on all United States howitzers and mortars. We offer a full spectrum of contract machining and assembly capabilities with our in-house machine shop and assembly department. Seiler Instrument can machine a few parts or manufacture complete assemblies and subassemblies to exact customer specifications. Through our extensive equipment and manufacturing capabilities, Seiler also specializes in refurbishment services. Refurbished optical fire control can extend the life of your weapon system at a fraction of the cost of new. In addition to our in-house machine shop and assembly department, we also have an in-house quality control department that inspects, tests, and certifies all products in accordance with customer requirements and specifications including MIL-SPEC (shock, vibration, environmental).

Along with manufacturing optical instrument assemblies and components, Seiler Instrument is a major distributor of surveying software and instruments, microscopes, and Zeiss Planetariums. Seiler Instrument is headquartered in St. Louis, MO.