Buescher True Tone. Considered Professional level. Blued steel springs. Blued steel insertion plates in flat spring channels. No “made in france” stamp anywhere though – not sure if they were manufactured directly by Buescher or possible a stencil from Conn or anyone else. Buescher True Tone Clarinet
Buescher 400 clarinets were stencils from Selmer USA. Similar to the Selmer Signet 100 or 200.