Recon cassettes are made from one piece, making them stiffer and even lighter than a Dura Ace cassette. You also have more options with the gear ratios. You can mount an 11-26 cassette or a 14-32.

Weights may vary 10% due to tolerances.

11-26: 11-12-13-14-15-16-17-18-19-21-23-26
11-28: 11-12-13-14-15-16-18-20-22-24-26-28
11-30: 11-12-13-14-15-16-17-19-21-24-27-30
11-32: 11-12-13-14-15-16-18-20-22-24-27-32
11-34: 11-12-13-14-15-17-19-21-24-27-30-34
11-36: 11-12-13-14-15-17-19-21-24-28-32-36 (32/36 alloy and non monoblock)
14-28: 14-15-16-17-18-19-21-23-24-25-26-28
14-32: 14-15-16-17-18-19-20-21-22-25-28-32
14-34: 14-15-16-17-18-19-20-21-24-27-30-34
16-28: 16-17-18-19-20-21-22-23-24-25-26-28