A bank is testing new technology that allows customers to make contactless payments for transactions up to £100 without a bank card or mobile phone.
Royal Bank of Scotland has developed biometric payment fobs that use fingerprints to verify transactions.
RBS, which has previously trialled biometric cards, said the fobs would allow payments above £30 without a card or mobile for the first time.
RBS will test the technology with 250 customers over the next three months.
Each fob is similar in size to a standard keyring and features a small fingerprint reader.
RBS said customers would be able to use them at existing contactless and chip-and-pin terminals.
When a fob is presented, a light indicates the fingerprint has been matched successfully.
In April, RBS piloted a biometric bank card that allowed customers to verify a purchase using their fingerprint.
Those taking part in the trial did not need to use a pin code to verify transactions of more than £30.
RBS said the card was designed to increase security and make payments at tills easier.
The bank described the trial as "successful" but has not said when that technology will be introduced.
David Crawford, head of Royal Bank Effortless Payments, said: "After the successful pilot of our biometric debit card we are looking at how we can further develop the technology and push the boundaries to integrate it into our customers everyday lives."
RBS is working with Visa and German-owned Giesecke and Devrient Mobile Security to develop the technology for UK customers.