The Scarpa Men's SL Active incorporates Scarpa's® new innovative Activ Fit technology Combining four elements; last, sole, ergonomic design & footbed, Activ Fit provides a new level of instant, out of the box comfort & performance. Built on the superb new BD last, the foot will stay continually supported & secure, aided by the new auto fit foam inserts in the heel area. Underfoot the Biometric sole provides the state of the art in sole technology, featuring dual density PU, produced in a highly scientific environment to maintain the highest performance & quality standards from the material. The midsole is reinforced with an additional moulded thermo plastic shank (TPU) & finished with the Vibram outsole. Glossary: Activ Fit Technology SCARPA's® experience & research guarantee absolute comfort in the new "ACTIVfit Technology" line: absolute in the sense that it turns subjective wellbeing into objective comfort. The new range of products takes quality up a notch in terms of performance, comfort, style & durability, specifically built for the maximum performance on any type of terrain. This model has all it takes to tackle backpacking, challenging trekking trips & lengthy hikes.BD Last Used in Kinesis, Kinesis Tech. A recently designed all-new modern last. Which whilst allowing for exceptional foot-hold also has enough volume to allow for modern levels of cushioning to be incorporated within the boot thus enabling both greater instant comfort & all day performance.