The glowing 20 adds another layer to the check.
Under a good quality ultraviolet light, the number 20 appears in bright red and green on the front of the note. The background stays duller. The feature works in exactly the same way on notes carrying King Charles III and Queen Elizabeth II.
The note adds features you can see and feel: sharp print, tiny lettering, raised Bank of England text, a purple T patch and three clusters of raised dots. A strong check uses several features together.
Three clusters of raised dots identify the £20 by touch.
Chris's 50km run can equip four students for university.
On Saturday, Chris plans to run from Fulham to Runnymede to fund four laptops for Adelle, Niavo, Tafita and Johany. Each earned a university place after growing up at Le Triomphe Children's Home in Madagascar. A laptop costs about £750 locally, which sets the £3,000 target.
Apple Pay gives each device its own card number.
Tuesday: when a card joins Apple Pay, the issuer creates a unique Device Account Number for that device. Add the same card to an Apple Watch and the watch receives another one. The full card number remains off the device and Apple Pay servers.