Diefenthal & Sohn take their hats off... ... and introduces itself as a tradition-conscious brand for hats with history and caps with style. Pia Diefenthal, a fourth-generation entrepreneur, and her partner Thomas Rüttgers, with their trained eye for quality and design, created a brand that can not only say “Made in Europe” on the label, but also attaches great importance to living tradition and sustainable processing .