AGT Gear Inner Cable PTFE Coated White Sram/ShimanoFeatures 31 Strand inner cable is softer, smoother, and more suitable for internal cable system 19 strands. Stronger structure than 19 Strand increases 10% tensile strength, more stable, more durability, and longer life. Lower friction smoothly works through the bicycle frame and brings perfect control performance. Ultra smooth and 3 times longer life after special high tech treatment