This special bundle set (set of 2) is a collaboration between Kaze no Mori and Hakuto Brewery to support the relief effort from the Noto Peninsula earthquake. Both bottles are Junmai Daiginjo.
 
Grey Label (Original Recipe by Hakuto Brewery) - Muroka (non filtered)
Purple Label (Collaboration with Kaze no Mori) - Muroka Nama Genshu
Both sakes use Kanazawa yeast, which is representative of Ishikawa Prefecture. They are also brewed using Yamada Nishiki rice from Ishikawa that could not be made into sake due to the disaster.
The original recipe is "brewed in soft water and pasteurized," while the collaborative version is "brewed in extra hard water and unpasteurized."
The contrast is interesting, so please enjoy the differences between them.