In order to achieve pads that are super comfortable to wear without feeling restrictive POC make use of VPD and a reinforced stretch fabric that allows the pad to conform to your body shape. You get hard shell style protection with the flexibility of a soft shell pad. You can hit your favourite runs at full speed confident that your POC pads have you covered. Visco-Elastic Polymer Dough VPD is used throughout POC's body armour range to offer extreme impact absorption allowing a lightweight and comfortable approach to cycling protection. VPD's flexible nature means that it will shape to your body, creating an unparalleled fit that is truly customised. The material hardens during impact, so the flexibility doesn't come at the cost of protection. VPD is able to maintain a high absorption level where other protection garments may see effectiveness drop after every knock. This means that POC's body armour gives you long lasting effectiveness for consistent protection so it doesn't let you down when you need it most. Delivering anatomical and ergonomical fit means a fantastic level of comfort that results in a huge amount of free movement that more rigid materials can't offer. VPD also offers great ventilation to keep you cool and comfortable when you're riding hard. Size guide: Measure from the centre of the ankle bone to the centre of the knee cap.