This is a reduced water cartridge. 2-year type Retail price: ¥16,500 I recently replaced the main unit, but it seems this cartridge is not compatible with the current model, so I am selling it. It appears to be compatible with Sanwa SANWA models RW1, RW2, RW5, RW7, and US-8000. The retail price including tax was ¥15,400. It is brand new, unused, and unopened. Thank you. I cannot offer a discount, I apologize.