Zachary Pozniak, from New York, is a fourth generation dry cleaner and often uses his social media channel to share his top tips and tricks of the trade.
And in one video he decided to tackle the common issue of white pit stains, knowing how hard it is for people at home to remove them.
He first produced a navy T-shirt with the white marks on the inside of the pits.
“First, start with dish soap and water and work that in,” he explained as he dunked a brush into the mixture.
Scrubbing the area down, he said that this would remove the oils from the deodorant.
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He then advised people to use a rust stain remover and shared that he used the Carbona Rust & Perspiration remover, which is a US product.
In the UK, there’s HG’s Stain Away for £7.90 on Amazon or Dr. Beckmann Stain Devils Antiperspirant & Sweat Mark Remover for £5.
“This is the key element with deodorant stains as most have metals that have actually rusted and caused this issue,” he said.
After applying the remover onto the area and scrubbing down with the same brush, he said you should wait for 15 minutes “if you can”.
“Then wash as recommended,” he said. “Inspect before drying.”
In the caption, he added: “Make sure to inspect before tumble drying.
“If that did not work repeat the process and allow the stain treatment to sit on the stain longer (overnight is best).
“If your stain is YELLOW at the underarm it is an oxidized sweat stain and will require oxygen bleaches. This guide will not help you”.
People were quick to comment as one person wrote: “Metals!! Of course! That makes so much sense!”
Another asked: “does this work on white shirts?” to which TikTok user @jeeves_ny replied: “It should but odds are higher that it looks yellow after.”
Another pointed out: “does this work on white shirts?”
He replied: “Aluminum doesn’t rust but corrodes. This process is known as oxidation. The resulting aluminum oxide is a thin, hard white layer !”
And a fourth added: “OMG you just saved my life”.