Book your Winter 2012 ski trip before 31/08/2011 and we will send you a Berghaus Powderkeg rucksack! The Powderkeg was designed with help from Olly, IFMGA mountain guide and director of Mountain Tracks. Simply book a winter trip worth more than £1000 with Mountain Tracks before the end of August and you'll receive a Berghaus Powderkeg. Book trips worth a total of £2000 and we'll even give you a second one!*

This is what Olly has to say about the sack and the design process...