Battery charge indicator: save batteries: you can simply test battery voltage to determine whether the capacity of the battery is low or high. it wont directly detect the battery capacity precisely. this will keep US from wasting perfectly good batteries throwing out good ones
Battery checker tester for household batteries: easy to red, colour coded meter indicates power level.
Battery tester: if needle does not move, check that battery is touching both before assuming.
9v battery tester: three result: red=replace, yellow=low power, green=good.
Small battery testers: widely used to test various household batteries such as aaa, 1.5v, 9v .5v button cells.
