Level 1 (range ~ 0.8 g/l corresponding to ~ 50 µmol/l)
Level 2 (range ~ 2.0 g/l corresponding to ~ 125 µmol/l)
Level 3 (range ~ 4.5 g/l corresponding to ~ 280 µmol/l)

Storage: +2 ... +4 °C

The controls are only produced to order.
Minimum quantity is 5 litres per level.