AeroJet S4 by Hon&Guan is a 4-inch (100 mm) mixed-flow inline duct fan for compact ventilation runs in grow tents and small spaces. It uses a quiet, efficient EC motor and includes a variable speed controller for 0–100% adjustment. The fan is rated at 146 CFM (approximately 249 m³/h) and operates on universal 100–240 V input. A compact housing with an integrated stand simplifies mounting to standard 4-inch ducting. Typical uses include hydroponic tents, heating and cooling boost, and general exhaust or intake where controllable airflow is needed. Pair with 4-inch carbon filters and ducting for odor control and complete ventilation circuits.