The Adey Magnaclean Professional 2 is a primary return filter, perfect for indoor use with a boiler heating system. This black filter unit, boasts an energy efficiency rating of A+++, making it a high-performance and eco-friendly choice for your heating needs. Designed for easy installation, the Adey Magnaclean Professional 2 is a reliable and efficient option for your home heating requirements. (USED Excellent condition)