William Grant & Sons is launching a neck collar promotion on its Three Barrels Rare Old French Brandy . The £30,000 promotion, which offers consumers the chance to win cash vouchers worth up to £100 per purchase, will run on 50,000 bottles over the Easter period. The vouchers will be redeemable in more than 19,000 high street stores. A direct mail campaign will coincide with the voucher promotion.