Plaintree Systems Inc. is a diversified company with technologies and manufacturing capabilities in structural design and aerospace. Its Specialty Structures division includes the Triodetic Group, which is a design/build manufacturer of steel, aluminum and stainless-steel specialty structures, such as commercial domes, foundations for unstable soil conditions and flood zones, for free-form structures, barrel vaults, and others; and Spotton Corporation, a design and manufacturer of high-end custom hydraulic and pneumatic valves and cylinders. Its Applied Electronics division includes Hypernetics, Summit Aerospace USA Inc. and Elmira Stove Works Inc. businesses. Hypernetics is a manufacturer of avionics components for various applications. Summit Aerospace USA Inc. provides high precision machining for the aerospace and defense markets. Elmira Stove Works Inc is a manufacturer of high-end heritage and retro-styled kitchen appliances under the brand names Northstar, Fireview and Heritage.