The Littelfuse KRDB424 Delay-On-Break Relay is a compact 120V time-delay relay designed for HVAC and electrical control applications requiring controlled equipment shutdown. Measuring 2 x 2 inches, it uses microcontroller-based timing to keep the output energized after the initiate switch opens, then de-energizes after an adjustable 1–100 minute delay. It is suitable for HVAC systems ... https://www.partshnc.com/krdb424-littelfuse-2x2-d-o-b-wrelay