This is a telephoto lens of reasonable cost for use with small reflex or hand cameras. Originally produced in 10" (for 2 ¼" x 3 ¼") and 12" (for quarter-plate) sizes it was later (c.1931) available in a 9" size and for 16 mm cine cameras. The aperture was f6 for the 10" and 12" and f6.5 for the 9".