Kair Ducting Adaptor 204mm x 60mm to 100mm - 4 inch Rectangular to Round Straight Channel Connector RECTANGULAR 204mm x 60mm The flat end is a male spigot and fits inside fittings. Requires rectangular duct connector Part: DUCVKC5608 to connect to 204mm x 60mm straight pipe - Part: DUCVKC5604 or flexible hose Part: DUCR3M/206/62. ROUND 100mm / 4 inch Circular end is a 100mm round male spigot that that fits inside 100mm round duct pipe Part: DUCVKC250. Allows you to convert between round and rectangular ducting systems. Made in the UK using high-quality Polystyrene/Polypropylene plastic. Max / Min Temperature: +60c / -15c. Easy to install and durable, just push-fit duct and fittings together. For permanent fixings, seal joints with silicone sealant or tape. Airflow performance independently tested by BSRIA or BRE. Suitable to use in compliance with Part F Building Regulations. Static Pressure Drop in Pascals: 15 l/s 0.96 Pa - 30 l/s = 3.84 Pa - 60 l/s = 15.41 Pa. Perfectly suited for ducting your Bathroom or Kitchen extractor fan, hydroponics, in-line extract Fans, tumble dryer, or cooker hood. This item can be used as a part of a long ductwork run for a variety of purposes including whole house ventilation, passive stack vent, positive input ventilation, air conditioning, HVAC, and Heat Recovery systems. Kair plastic rigid ducting is perfect for DIY and Trade use and provides superior airflow performance and durability versus flexible duct.