Gardeners can give litmus paper the boot with the pocket-sized Checker
pH Tester from Hanna Instruments! This affordable but reliable device
features simple two-point calibration and measures pH from 0.0 - 14.0,
with a resolution of 0.01 and ±0.2 accuracy range. Unit includes
replaceable electrode, batteries and instructions. Tester and electrode
protected by six-month manufacturer's warranty.