The Baxi seal kit is designed for use in the Solo HE & HE A, Solo IE, Solo IE ERP, Main HE A, Promax SL ERP, Combi (condensing), Promax, Promax SL, Main Heat ERP, Gold, Gold ERP, Precision, 100 He, and Barcelona boilers. Seals are used in many different areas of the boiler to join parts to pipework. Among other sections, heat exchangers and gas valves require these parts to prevent gas and water leaks.