The 83500-90 part from Eaton is a type of 45mm x 45mm IEC Contactor Accessory consisting of one Auxiliary Contact Block and one Endplate, sold as a part of Eaton's 300 series product line. This part can be used with a range of Eaton's contactors, and is an ideal solution for controlling a variety of loads such as motor, fans, and pumps. This part is designed to meet applicable standards like IEC 60947-4-1 and CE, CSA, and UL requirements, while providing reliable and long lasting performance. Additionally, it is RoHS Compliant, making it very safe and easy to use.