I think that you really need a 6 inch fan for a 4x4 tent. Here is a 6" Vivosun on Amazon with accessories for $127.50 https://www.amazon.com/VIVOSUN-Ventilation-Inline-Controller-Ducting/dp/B08WZGLGYQ/ref=sr\_1\_3\_sspa?crid=OD8RBFCDOR82&keywords=ac%2Binfinity%2Bventilation%2Bkit&qid=1663714347&sprefix=ac%2Binfinity%2Bventilation%2Caps%2C166&sr=8-3-spons&ufe=app\_do%3Aamzn1.fos.f5122f16-c3e8-4386-bf32-63e904010ad0&th=1