With advancement of technology, many office devices had become affordable. Purchase price has gone down so that many devices are not subject to depreciation. The tax code in Japan allows a one-time expense write off for devices which unit price is below JPY 100,000. The key here will be the unit price. Ask your tax accountant would this be including consumption tax for your company.
For devices and equipment, unit price falling between JPY 100,000 and JPY 200,000, accelerated depreciation of 3 years is allowed. Confirm with your tax accountant on the condition of such benefits being applied.
For small office supply items which are periodically purchased, even if they have not been used or consumed, under some conditions, you will be able to expense them at the time of purchase.