If you're referring to the early Sears, Roebuck & Co. brand, my understanding is that "Fulton" tools - and even those marked or marketed deceptively as "Fulton Tool Co.", were, just like "Dunlap", "Merit," and the more famous and popular "Craftsman" to follow, made by OEMs under contract. Diamond and Bemis & Call made "Fulton" adjustable crescent and monkey wrenches, K-D made "Fulton" pliers, and so forth. I don't know who made "Fulton" vises. Reed is a good bet, since they made later "Craftsman" vises. But you might want to consult more hard-core Craftsman guys on the Long C thread, more hard-core vise guys on the Mega Vise thread, or both.