Fantech FR 110 Inline Centrifugal Duct Fan, Molded Housing, 4"

The fans feature a fully sealed plastic housing. The housing is joined via a vibration welding process. The process uses transverse, reciprocating motion at the point of contact between the housing’s inlet and outlet pieces. The friction produces heat that melts the thermoplastic material at the interface. The melted material quickly re-solidifies, resulting in a fused, single-piece housing. The fused seam is inherently air tight, very strong and permanent. No screws or adhesive is used to join the housing pieces. An air-tight fan ensures that efficiency is not lost and contaminants are not spilled due to leakage.