Compur #00 26.3mm. This lens board is suitable for Linhof Master Technika 4x5 - Wista 4x5 - Toyo 4x5 - Intrepid 4x5. Ilex #3 50.42mm 1.985" 1 7/8" = 1.875" Kodak 10" Comm Ektar f/6.3. The Lens board has a 5mm down off c enter hole except the Copal #3 size which is too large.
eBay