The OHAUS ST20M is a multi parameter pen meter that directly measures pH, conductivity and temperature as well as provides conversion measurements for TDS and Salinity. These fully waterproof pen meters combine measurement capabilities of two testers in one convenient pocket-sized unit. Great for water, laboratory or plant use, the ST20M features a single-junction pH electrode and a pin-style conductivity probe for longer usage and durability.

Pen meter includes electrode, protective sensor cap, four AG13 1.5V batteries, and wrist strap.

Features include:

• Auto- shutoff
• Low battery indicator
• Waterproof reated to IP67
• Easily replaceable electrodes 
• LCD display
• Dimensions (LxWxH) 185 × 45 × 38 mm