Convertible Anastigmat f6.8 lens, Series II for 5x7 format.
Focal length of 7.5" with both cells, 18" with front only, 12" with rear.
Aperture scale has settings for all 3 configurations.
Ilex shutter works well with 2 exceptions: 1) shutter release lever doesn't work, but cable release works fine; 2) B, T don't always work as expected. If set halfway between B and T, the shutter will work reliably in B mode.
Glass is good, with a very small amount of edge separation on front and back cells.
$75 plus postage. Paypal accepted.