This tester reads on the front:<BR>"Trade Mark MAC METRIC APPLIANCE CORP.<BR>Patent May 23,1916"<BR>3" wide between the contacts, 7" from tip to handle end.<BR> Makes for an interesting collectors item.<BR>for sale on ebay <A HREF="http://cgi.ebay.com/ebaymotors/aw-cg...em=1810208145" TARGET=_blank>http://cgi.ebay.com/ebaymotors/aw-cg...1810208145</A>