The DO600-K is a convenient kit which adds versatility for measuring dissolved oxygen in laboratories or out in the field with a 16-Foot (5m) extension cable and probe weight guard for taking easy measurements in tanks or streams. Complete with ExStik® II DO meter, DO electrode, protective sensor cap, DO603 replacement membrane Kit, 16-Foot (5m) extension cable, weighted probe guard, four 3V CR-2032 batteries, 48-Inch (1.2m) neck strap, and hard carrying case.