If Mars Bars are your chocolate treat of choice this is a brilliant offer, as you can get a Case of 48 of the bigger 51g bars for only £20.64 at Amazon! Just tick the £6.85 off voucher under the list price to get them for this lower price.
These big 51g bars would set you back 75 each at Tesco, but with this offer you're paying only 43p for each bar - and with free delivery too!
The voucher will have a limited number of redemptions, so once they're all used up the price will go back up, so don't leave it too long to get your order in if you want some.
Free delivery is included as this is over the £20 minimum spend.