Just had this email from Royal Mail:
Our Medium Parcel size measures a generous 61cm x 46cm x 46 cm, which makes it ideal for larger items such as boots, coats and rucksacks. What's more, we've cut the cost by nearly 40%* so you can now send much more for much less with Royal Mail.
Save £3.11* on every Medium Parcel you send
Now only £4.89 for 2nd Class up to 2kg.
http://www.royalmail.com/parcel-tari...elq_cid=766184