The SRAM PG-1050 10-Speed Cassette offers an innovative approach to 10-speed cassette design. SRAM's cassette performance is optimized by material choice, tooth profile & shift ramp design for a quick & positive index shifting. The cassette shifts efficiently & positively in all high performance situations. The new cassette features a semi-spidered construction for a maximum stiffness to weight ratio & is available in many optimized configurations to best match a wide variety of uses. Power Glide ll cassette technology has been optimized for off-road. More reliable, more durable, better performing. Thanks to an optimal tooth profile & shift ramp design for quick & positive index shifting. Go climb a mountain.