The new security aims to act as a deterrent for people who fail to pay for items in their shop.
Failing to scan items at self-service checkouts or scanning the item as a cheaper alternative remains a widespread problem for supermarkets and one in four shoppers who use self-service tills has admitted to failing to pay for an item, according to VoucherCodesPro.co.uk.
The study also found how Brits are stealing £3.2 billion worth of goods from self-service tills every year – or around £5 per person per month.
Sainsbury’s said in a statement: “This is in hundreds of stores and has been in some for almost a year.
“The safety of our customers and colleagues is extremely important to us, which is why we invest in a range of measures to keep everyone safe.”