Specifications:

• Shimano Dura-Ace Cassette 7900 
• CS-7900
• 10 speed
• Steel/Titanium cogs
• 11-12-13-14-15-16-17-18-19-21t
• Shimano HG Freehub 
• Approx Weight (w/ lockring): 156 g
• NOS, new Shimano cassette in original box. May have some minor evidence of shelf wear from storage, though there appears to be none of note.