I've added only two of these duvet's and 3-face towels (on offer) and end up to pay only £31. Actually, it cost me only £12 for each duvet (Excellent price for good company Super Kindsize duvet).
Not sure if it will work, add some other item to make the cost £40 and use the code TDX-VM3N to take £10 off. When you will receive the item, return the other item..:)
Save £10 when you spend £40 with eCoupon TDX-VM3N or save £20 when you spend £75 with eCoupon TDX-MJYP on selected Home, Cook & Dine
Enjoy a deliciously comfy night's sleep with the deep sleep duvet from Silentnight. Filled with spiral fibres to ensure extra depth, this cosy duvet is finished with a 70% polyester and 30% cotton blend cover for softness and breathability. With a 13.5 tog rating, the deep sleep duvet is perfect to snuggle up to during the colder months. It is non-hypoallergenic for a cleaner, healthier night's sleep, and machine washable for easy care.
Read more at http://www.tesco.com/direct/silentnight-deep-sleep-135-tog-duvet-super-king/321-8483.prd#l070IOYcriFuXHad.99