This is a Darlot portrait lens, approx 13" focal length, f4.5. Perfect for 8x10 portraits , possibly even 11x14 but I don't have one to try it on. Can be fixed to a 6x6 lens board, so will fit a Kodak 2D 8x10 board or a Deardorff board. The prices on Darlots have been very strong recently, so here's a chance to get one you might not be able to afford in a year or two.
Details: Focal length is approx 13". Approx f4.5 wide open, and with the included stop, around f6.6. Flange is just under 6" OD (see photo of it with a 6x6 board below; board not included). Weighs a little over 4.5 pounds. 8" tall. Easy to disassemble for cleaning. Includes: the hood, flange, lens and one waterhouse stop.
The brass is labeled for Darlot Opticien and BF & Co (a US importer). The front lens element has Darlot penciled around the edge as it should, and the owner in 1954, a professional photographer, also inscribed his name and location there as well (Oil City, Pennsylvania).
Known Faults: There is about 1-2mm of separation around the edge of the front element. In one spot, it pops out to maybe 4mm. There is a photo below where I tried to capture this, but the separation is not in a position to adversely affect your photos. The brass is obviously scuffed up in places.
Price: $519 US via USPS money order. I'll ship overseas but you have to use paypal as a gift, and pay international priority shipping and insurance.