Based on this product's specifications, here are some alternatives and similar models
Round Duct Connector Ø100 mm airRoxy 02-464 (MPN 02-464)
Summary description:
Round duct connector for ventilation and air distribution systems, airRoxy model 02-464 with nominal diameter 100 mm. Designed to join or extend circular ducts and fittings, providing a straight, sealed connection for forced ventilation, extraction, or HVAC applications. Suitable for residential and light commercial installations where a 100 mm round connection is required.