Voltage and current and full charge indicator. Main point I got these was for the current adjustment, to turn down for less heat on projects and testing works good. Form factors a bit large wish there was a smaller unit size is every thing when DIY projects. Also going to test if the full charge indictor stops the voltage flow for charging batteries ( would like to be able to walk away for coffee or other things and not have to worry)If so this will be worth the $
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