ANSWER: Every 4 weeksWin a BRITA Glass Jug and a year's worth of ALL-IN-1 filters worth £114! BRITA want to keep the excitement going for the year ahead, so we're allowing you to win a BRITA Glass Jug and a year's supply of ALL-IN-1 filters.BRITA recommend changing your filters every four weeks, so this prize will keep you going for a year. To enter the competition, click the "GET FREEBIE" button below and answer the question correctly to win.Get Freebie