VIVOSUN’s AeroZesh G4 Inline Fan 4″ with E12 Speed Controller is a 4-inch mixed-flow EC duct fan designed for tent ventilation. The E12 PWM controller provides 10 selectable speeds plus three ON/OFF cycle modes and retains settings after power loss. The 4″ model is rated at a maximum 195 CFM, equivalent to about 331 m³/h, and operates at approximately 39 dBA. Power draw is 20 W from 110–240 V, 50/60 Hz, with IP44 ingress protection. The package includes a wired environmental probe and 1.8 m power cable with a 3 m controller lead for flexible placement. Flange size fits standard 4″ ducting; overall housing measures 11.8 × 7.8 × 7.4 in. Intended for continuous grow‑space exhaust or intake with optional GrowHub upgrade.