The Onset MX2001TOP HOBO Freshwater Water Level Data Logger (Top End) includes an internal barometric sensor for barometric compensation and for calculating water level data. The vent has a hydrophobic membrane which allows the logger to sense barometric pressure while keeping water out. This logger should not be submerged under water for longer periods of time.

• Requires MX2001 sensor (sold separately)
• IP67-rated weatherproof
• Vented design