![linhof technika iv graflok linhof technika iv graflok](https://www.fleaglass.com/wp-content/uploads/2018/08/P1570400-800x600.jpg)
The shutter has a large diameter externally threaded shaft about the diameter of the hole on the board. This is required to mount the lens to the board rigidly. You can look on eBay, and will find the from about $20-? If you’re buying a board less lens, the other important thing to check is if the lens includes a retaining ring. So you would probably need a Technika board drilled for a #0 shutter. The Caltar in your link looks like a Copal 0 to me, but I’m far from an expert. The 00 and 0 shutters have the usual progression of shutter speeds your used to from smaller cameras. You can also look at the pictures and use some visual clues to determine the shutter. Fortunately Copal and Compur seemed to match sizes, so a Copal 0 and a Compur 0 are the same hole size (and I assume the same lens element mounts and spacing, but I’ve never really confirmed that.).
![linhof technika iv graflok linhof technika iv graflok](https://assets.bigcartel.com/product_images/295962180/s-l1600+_3_.jpg)
Some lenses changed over the years, or it’s possible the lens was remounted in a new shutter. First, you can look online to see if you can find out what shutter was normally sold on the lens-though be careful. If the seller doesn’t mention what shutter is on the lens, you can do a couple things. That’s because each shutter has a standard hole size.
![linhof technika iv graflok linhof technika iv graflok](https://i.pinimg.com/736x/e4/b2/91/e4b2913d161e49b97623870739fa7900.jpg)
But usually you’ll see it listed as “Copal 0” or “Compur 1” or similar. Some places like KEH list it (when listing used boards for sale) with an actual measurement, I.e. If you’re buying a lens without the lens board you need, the first thing you need to determine is the shutter hole size. When I’m looking for lenses on eBay, I tend to gravitate towards ones that already have an attached Technika lens board, because it saves me time, effort, and sometimes cost. They’re used in Technikas, Technikardans, Shen Haos, Wistas, and other cameras. You’ll notice the they have the lower corners clipped. Click to expand.Technika IV and later use a very common, and visually distinctive lens board.