The underlying index for this product is a total return index, engineered to reflect two components: (1) the performance of a continuously rolled portfolio of specific silver futures contracts, selected as those anticipated to be the most liquid near-term contracts three months into the future, following a predetermined schedule; and (2) the return equivalent to the weekly announced interest rate for designated 3-month U.S. Treasury bills. These Exchange Traded Notes (ETNs) are medium-term, senior unsecured debt obligations issued by Barclays Bank PLC.