No markings noticed on the vice to identify the maker. There is a signature Francis L. Which is lightly engraved and hidden well. Very nice precision machined piece. It is approximate measures 1 7/8 square x 3 5/8 very close to a starrett if is not. I believe the threaded holes are 3/8 16. The item “MACHINIST LATHE TOOL MILL. RARE vintage V Block and Clamp lighty signed threaded” is in sale since Monday, February 17, 2020. This item is in the category “Collectibles\Tools, Hardware & Locks\Tools\Machining”. The seller is “goodstuff-richard” and is located in Millers Falls, Massachusetts. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, China, Sweden, South Korea, Indonesia, Taiwan, South africa, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Bahamas, Israel, Mexico, New Zealand, Philippines, Singapore, Switzerland, Norway, Saudi arabia, Ukraine, United arab emirates, Qatar, Kuwait, Bahrain, Croatia, Malaysia, Chile, Colombia, Costa rica, Dominican republic, Panama, Trinidad and tobago, Guatemala, El salvador, Honduras, Jamaica, Antigua and barbuda, Aruba, Belize, Dominica, Grenada, Saint kitts and nevis, Saint lucia, Montserrat, Turks and caicos islands, Barbados, Bangladesh, Bermuda, Brunei darussalam, Bolivia, Egypt, French guiana, Guernsey, Gibraltar, Guadeloupe, Iceland, Jersey, Jordan, Cambodia, Cayman islands, Liechtenstein, Sri lanka, Luxembourg, Monaco, Macao, Martinique, Maldives, Nicaragua, Oman, Pakistan, Paraguay, Reunion, Uruguay, Russian federation.

• Country/Region of Manufacture: Unknown
• Brand: proto type no markings ?