Measure temperature and dissolved oxygen simultaneously using highly accurate thermistors and YSI's proven polarographic technology for dissolved oxygen. The fastest DO response times on the market.

Measurements are fast and easy with one-hand operation, an easy-to-use backlit display, automatic push-button calibration, and a weighted, quick-sinking probe. The YSI550A DO has a built-in calibration chamber, low-battery indicator, direct salinity, and altitude compensation. The instrument provides simultaneous readings of oxygen and temperature. Dissolved oxygen readings are automatically compensated for temperature.

Screw-on cap membranes make membrane changes easier than ever. The PE membranes are also faster responding and require far less flow dependence.

The replaceable electrode decreases any down time due to old or damaged electrodes. Simply unscrew the old electrode, replace it with a new one, and calibrate! No need to send it in or to replace the whole cable assembly. The cables are now even stronger!

If you're interested in dissolved oxygen measurements please take a look at our NEW Professional Series products Pro20 or optical DO handheld ProODO.

Features:

• Field-replaceable DO electrode modules
  
• Screw-on cap membranes
  
• IP-67 case
  
• Over 2000 hours battery life
  
• Calibrate in either mg/L or % saturation