If you have a voucher code, you can enter it when you are in the Shopping Cart, this is when you URL is: https://www.tyroola.com.au/cart/

This field is case sensitive, so if you voucher code is 'DUNLOP_SPECIAL' then the following will not work: Dunlop_Special, dunlop_special, DUNLOP_Special, etc

Only one voucher can be applied at a time, therefore if you have a voucher, but also have added tyres in a buy 4, pay for 3 deal, then your new voucher will override this deal (cannot 'stack' vouchers/offers).