SD217 is a brand of industrial control relays manufactured by Struthers-Dunn. The relays are designed to provide efficient circuit control and switching functionality, which is used in a variety of industrial applications. SD217 relays are designed with high-quality materials, making them highly reliable and dependable for a range of demanding applications. They feature numerous contact configurations, such as single pole double throw (SPDT), single pole single throw (SPST), normally open (NO), normally closed (NC) and changeover (CO). The relays are available in a wide range of voltage, current, and form-factor sizes.