NOTE - when previewing, please zoom in. The dithering of the grey areas is an artifact of the viewer, the book does not look like this.
The famous Gruen 448 material catalog. This is the 1948 version of the material catalog and has a slightly different format than other versions. For example, you get a picture of each movement in this edition. Get the same colorful cover and an interior consisting of clean, white, more durable paper than the originals. A great edition to your horological library and a must-have for any Gruen restorer or tinkerer.
