Shop Fjallraven Mens Karl Trousers. Karl is an outdoor trousers series that can be used anywhere, such as while hiking in the mountains or at your summer cabin. This model is made of durable G-1000® Silent fabric and has a brushed finish. The trousers have a low waist and regular fit. Pre-shaped knees and raw length. Two side pockets, two back pockets, one large leg pocket for maps and one smaller pocket for multi tools. Raw length at the leg ends allows you to adjust the length of the legs exactly as you wish.