Potassium Sulphate is a slow release high quality Potassium ideal for lifting Base Saturations. 

It is the most common mineral required for most soils. All Fruit and Root crops require this is abundance as they are largely filled by potassium. Fruit like Kiwifruit are 55 +% potassium (dry weight) and potatoes are even higher.  

Potassium 42 %

Sulphur 18%