If anybody happens to have a UL white book around could you please check out a Thomas and Betts #5060 box and see what the listing says about its use. Thanks in advance.
Basically, everyone has access to the UL "White Book" content s through: http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/index.htm
Using "Thomas and Betts" as the Company Name and "5060" as the Keyword, I found the box listed under Nonmetallic Outlet Boxes and Outlet Boxes and Fittings Classified for Fire Resistance