Hit back with National Savings 104 That money in your pocket can become part of another British fighter, another gun, another shell. Don't spend it on yourself. Lend it to the country. Buy National Savings Certificates. Certificates are easy to buy and easy to cash at short notice. They cost 15/- each and increase in value till in 10 years they are worth 20/6. This represents a rate of interest of £3.3.5d. per cent, which is free of Income Tax. Certificates may be bought at Post Offices, Banks and from Honorary Official Agents in shops and stores.