Fizik Arione R5 K:ium Rails Road Bicycle Saddle K:ium is the combination of a particular metal alloy, a specific tubular design and a special finishing process which increases fatigue performance on the rail surface. Wing Flex Technology- Engineered flexibility along the edges where the inner thighs contact the saddle. Carbon reinforced nylon shell for excellent strength and durability For The Snake: Flexible Spine Weight: 205 g