Securely fasten your 120mm or 92mm fan to 4 duct tubing with the simple, but effective adapter. These are made from high quality molded thermoplastic (not 3D printed). The interior of the shroud is ribbed so most 4 ducting will be held without the additional use of screw holes and included screws.
Coolerguys 120mm or 92mm Fan to 4 Ducting Shroud Funnel with Clamp for Greenhouses, Enclosures, Crypto Mining, and More
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