The SD oxygen sensor type Oxi L 400 is based on the latest luminescence technology. The optical method enables a drift-free determination of dissolved oxygen with highest precision. There is no need to refill an electrolyte, thus eliminating cumbersome maintenance tasks. Since no oxygen is consumed during the measurement, the sensor is immediately ready for use without the need of sample stirring. The durable membrane head is insensitive to other gases and sulfide-containing samples making the sensor a real all-rounder for several applications. The sensor is compatible with Karlsruher bottles NS 19 / 26 and is ideally suited for the determination of dilution BOD. Possible temperature influences are easily compensated by the built-in NTC 30 kΩ thermistor.