Question about Bosch Professional Zubehör Freehand burr set. 8 mm shank. 30 pieces

What is the difference with this article: https://www.galaxus.ch/en/s4/product/bosch-professional-zubehoer-30-piece-milling-cutter-set-6-mm-shank-for-hand-milling-cutters-cutters-11551352?supplier=406802? The other one is 6CHF more expensive for some reason?