You can purchase the Keyball series through Furusato Nozei (hometown tax donation).

Thank you for your continued patronage of the Shirogane Lab Web Shop.
We are pleased to announce that all three models of the Keyball series (Keyball39, Keyball44, and Keyball61) are now available for purchase through Furusato Nozei (hometown tax donation) in Hida City, Gifu Prefecture, on the following Furusato Nozei handling sites.

Furusato Nozei Handling Sites
Rakuten Furusato Nozei / Furusato Choice / Furusato Navi / Yahoo! Furusato Nozei / JRE MALL / Saison Furusato Nozei / au Pay Furusato Nozei / Satofull / Amazon Furusato Nozei

*Only Keyball44 is available for purchase on Amazon Furusato Nozei.