We don’t know of a specific name or model for this rucksack; Mick Tighe remembers them being called the Tiso Sack and it seems they were made by Karrimor to a Tiso specification. Tiso’s were, and still are in 2010, Outdoor Shops, initially based in Edinburgh. The Joint Services Mountain Training Centre in Fort George had loads of them in the 1970’s and Lochaber Mountain Rescue Team used them extensively in the 1970’s & 80’s for their casualty bags, and big stretcher lowering ropes. This one probably came from there. The large blue pull out section was designed to make the sack part of an emergency bivouac system with your feet in the big bag(having emptied it!) and the blue bit pulled around the body. They were certainly very hard wearing.