Battery-powered CoolPoint vortex-shedding flowmeters for water, chemicals and corrosives run on 3 AA alkaline or lithium batteries. The expected battery life is six months for alkaline or two years for lithium. They indicate flow rate or total on an LCD screen, and range in size from ¼ in. to 2 in. with maximum flow ranges from 4 gpm to 200 gpm, maximum pressure of 300 psi, and temperature ranges from 32 ºF to 210 ºF