Drive around the streets of Kuwait and you won't see these women. They are behind closed doors, deprived of their basic rights, unable to leave and at risk of being sold to the highest bidder, APA reports citing BBC.
But pick up a smartphone and you can scroll through thousands of their pictures, categorised by race, and available to buy for a few thousand dollars.
An undercover investigation by BBC News Arabic has found that domestic workers are being illegally bought and sold online in a booming black market.
Some of the trade has been carried out on Facebook-owned Instagram, where posts have been promoted via algorithm-boosted hashtags, and sales negotiated via private messages.
Other listings have been promoted in apps approved and provided by Google Play and Apple's App Store, as well as the e-commerce platforms' own websites.
"What they are doing is promoting an online slave market," said Urmila Bhoola, the UN special rapporteur on contemporary forms of slavery.
"If Google, Apple, Facebook or any other companies are hosting apps like these, they have to be held accountable."
After being alerted to the issue, Facebook said it had banned one of the hashtags involved.
Google and Apple said they were working with app developers to prevent illegal activity.
The illegal sales are a clear breach of the US tech firms' rules for app developers and users.
However, the BBC has found there are many related listings still active on Instagram, and other apps available via Apple and Google.