KOLJA BOOKBAG BY KREJCI When Dutch designer Doreen Westphal received a bag full of inner tubes as a joke Christmas present she started to play around with the material, which resulted in her first inner tube bag. Kolja is part of the Tubus Collection. Outside material: used inner tubes. Inside material: felt (petrol or mustard). 1 front compartment and many other surprises. 10"h x 7"w $120.00