COVID-19 Update: HART Unions is open for business and fully operational! Call us at 1-800-769-0503 or email us at

Welcome to HART Industrial Unions!

HART Industrial Unions, LLC is the leading domestic supplier of Sure Seal O-Ring Unions. We have a extensive selection of information and technical data about our products available on the left. If you have any questions or if we can help you further, please contact us at 1-800-769-0503.