Based on this product's specifications, here are some alternatives and similar models
Chimney roof pipe WADEX Roof101, diameter 120 mm
Summary description:
Chimney roof pipe WADEX Roof101 with 120 mm diameter designed for venting and exhaust of combustion gases. Suitable for installation through roof structures to connect flue systems or appliance exhaust outlets. Key characteristics include circular cross-section and standardized 120 mm nominal bore; used in residential and light-commercial heating, ventilation and chimney applications.