The Ferroli 39810370 Air Vent Separator is a key component for residential boilers, specifically designed for the Optimax 25C, 25S, Maxima 35C, and 35S models. This vented separator from the trusted brand FERROLI ensures proper air ventilation in heating systems, maintaining efficiency and preventing scale buildup. With its reliable performance, this air vent separator is an essential part of any central heating system in a home.