[. . . ] This product, including accessories, may change due to upgrading without prior notice. [. . . ] This product, including accessories, may change due to upgrading without prior notice. â· Since this product is not waterproof, do not use it or store it where fluids, for example water, can splash onto it. Press twice to clear any residual values and calculation instructions in the calculator. ) A tax rate can be set (or changed) with a number containing up to four digits. However, the set tax rate may be changed or lost if the battery is consumed largely. [. . . ] ) A tax rate can be set (or changed) with a number containing up to four digits. [. . . ]