The HIVENT from H2S Control is a passive vapor phase odor control unit that easily attaches to a lift station vent. It uses HISCENT, a safe blend of all-natural essential oils to neutralize odors emitted from the vent. When the lift station pumps are off and the wet well level is rising, the odorous air passes through and is neutralized before being discharged into the environment. When the lift station pumps are running and the wet well level is dropping, clean air is drawn through and into the wet well along with HISCENT neutralizing odors within. It treats the air twice using no water or electricity, only the natural flow of air through the unit. It is made of corrosion-resistant aluminum, requires no maintenance, and uses just two to three gallons of HISCENT per year. 407-628-1880; www.h2scontrol.com.