Maker of a design of locking nut, of Salisbury Sq, London (1916)
of Market Harborough.
1913 Vislok nuts first offered for sale.
1916 Offered a range of safety nuts which were used by a wide range of clients. Based on the coincidence of address, and the fact that the advertising was handled by Haddon Advertising it seems likely this company was part of Haddon group of companies