Important Things to Know About Low G Tuning on Ukulele.

You only have to change one string to make the sound of your ukulele much lower pitched! Yes, you can buy just one string and do the job yourself! Use the same setting on your clip-on tuner for GCEA and Low G,CEA.
Aquila New Nylgut AQ-9 Concert Ukulele String - Low G - 4th String amzn.to/3KH8by3 Amazon affiliate link. Commission paid at no extra cost to you.
If I'm changing out four strings and want low G, I generally buy Ph.D. strings on eBay. You will find four string sets for all size ukes.
PHD Ukulele Strings Sop / Con LOW G Daniel Ho Jason Arimoto
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PHD Ukulele Strings TENOR LOW G Daniel Ho Jason Arimoto
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PHD Ukulele Strings BARITONE GCEA Low G Daniel Ho Jason Arimoto
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Important Things to Know About Low G Tuning on Ukulele.