Originally a vertical-cut product, Operaphone made the switch to lateral-cut technology in the summer of 1919, after other labels such as Brunswick and Gennett had decided to challenge the Victor/Columbia duopoly head-on. However, in spite of its claims to be 'Music For Everybody,' and suited to 'Play On All Talking Machines,' Operaphone had disappeared by 1921 (the later Canadian Opera-Phone label was likely unconnected). from http://www.tedstaunton.com/labels/1910-1919