The Carlyle 5H40-481 Piston Ring is a set of 16 high-quality replacement parts designed for HVAC and refrigeration systems. Manufactured by Carlyle, a trusted brand in the industry, these piston rings are essential components for maintaining optimal performance and efficiency in your systems. With a unit quantity of 1, this product ensures you have all the necessary components to get your HVAC or refrigeration system back up and running smoothly.