I have the craftsman
clmapmeterAs long as the aaa alkaline batteries are 1.42 volts or above it is accurate reading amperage.
reading low currents accurately seems to require placing clampmeter right next to wire being measured, and zeroing the meter, then clamping it over the single wire and keeping the wire in center of the clamp. It does drift if left in place for a while especially in noisy electrical environments.
In noisy environs, Unclamping it and not having any wire run through it will read a few hundredths off, requiring a rezeroing and re clamping.
Gefwif.
Should be said I do not have a calibrated meter to compare it to.