can anyone guess the specs on this lens

[part2wanksta]

there is this lens on ebay and i was wondering if anyone could guess the specs.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7575500001&rd=1&sspagename=STRK:MEWN:IT&rd=1

 

[part2wanksta]

the guy said the diameter was about About 3-1/8 in.