CoolNet® Headband Ellipse Delft Multi: CoolNet UV® Headband Ellipse. Preserving its recycled nature made of fusion joined fabrics, our new BUFF® Headband has moved one step forward. Still comfortable and breathable, it will fit even better to your head thanks to its new Ellipse design. Whichever activity you choose to practice under the sun, you will stay cool and protected. CoolNet UV® technology pulls sweat away and wards off skin irritation, apart from preventing hazardous exposure to the sun. Comfort and protection, all-in-one.