Viomi Technology (VIOT), a provider of home water services in China, said Friday it expects preliminary H1 revenue to surpass 1.4 billion renminbi ($194.9 million), up more than 70% year over year.

The expected increase is mainly driven by the growing sales for household water purification equipment, "further supported by national subsidy policies," the company said.

Viomi shares were up 8.9% in recent premarket activity.