From the 23rd September through to 6th November 2011, every two cases of Tetley 2x1100's and every seven cases of Envelope 250's qualify caterers for a £10 voucher from either Argos or Marks & Spencer. There's no limit to how many times you can claim, the more cases you buy, the more vouchers you get. To make the most of this offer visit www.tetleyforcaterers.co.uk/xmas to download an application form and return it completed to the Freepost address provided, along with your proof of purchase, by 21st November 2011