Nordenmark Adventure's traditional map holder for mountain bike orienteers and adventure racers. Light weight and secure. Great performance. At 500 grams, the Extreme fits both standard and oversized handlebars, up to 35 mm diameter. The map board fits up to 22.5 by 30.5 cm map and turns a full 360 degrees to allow the user to orient the map. Mounting on bike is with wing nuts - no tools required.