D. FENSTEC®, TECHNICAL UNDERGARMENTS SPECIALLY SUITED FOR HUNTING AND SPORT D. Fens® fibres In hollow POLYPROPYLENE, a revolution in functional-technical undergarments. - Summer and winter, the D. Fens® fibre quickly eliminates sweat and keeps the skin dry at a constant temperature. - More thermal than wool and more thermal than all other synthetic fibres thanks to the air it contains in its hollow sections. - It absorbs nearly no moisture (0.05%) and quickly expells sweat to the outer layers - Polypropylene is the lightest fibre, but hollow D.Fens® is even lighter still. - D.Fens® fibre, 100% hollow polypropylene, has shown during tests that it is even better than other natural or synthetic fibres because of its unique functional technical characteristics.