What are those "V" shaped things on the New England Patriot's field?

Gillette does sponsor their stadium. “V” is the roman numeral five.. And they now make a five blade razor.

http://www.businessweek.com/bwdaily/dnflash/sep2005/nf20050915_1654_db035.htm

If you are talking about the things at the fifty yard line, they are part of the logo for the stadium. they are stylized representations of a tower and bridge at the main gate of the stadium. I assume they represent a lighthouse or famous tower and bridge in Boston. Check out the patriots website and click through the stadium links for more.