SIM card is available in three sizes: mini (regular), micro, nano.
Make sure selecting the right size to suit your device.
If you buy wrong size of the card, most providers do not exchange it, nor give a refund for any reason.
Meanwhile, if you use a rental SIM card service, some providers may exchange it or give a refund even after you received.

First, your device must be UNLOCKED to use SIM cards.
To unlock your device, you need to contact your device suppliers or device manufacturers.

In addition to that, your device must support one of the following frequency bands.

4G(LTE): Band 1 (2100MHz), Band 19 (800MHz), Band 21 (1500MHz)
3G(W-CDMA/HSDPA/HSUPA):Band 1 (2100MHz), Band 19 (800MHz)

In Japan, available frequency bands vary depending on places.
If your device does not support the frequency band of a place, you might not get connected.
Before you go out, we highly recommend you to check compatibility of your device by using service below.

FrequencyCheck

Same as the case of wrong card size, most providers do not exchange it,
nor give a refund for any reason once after you buy it.
If you get around Japan especially local places, we recommend you to rent a Mobile WiFi from a rental service provider.

Some prepaid SIM providers attention to delivery in their websites.

Postal code, Room number
When the address is not completed, the package will be returned to the provider
When the postal code is not correct, delivery will take more time than usual.
If it is an apartment, it should include the apartment name and the room number.

Mailbox
Get the key or the key number of the mailbox from your host.
The packeage will be posted in the mailbox of residence.
Mailboxes are often located on the ground floor of an apartment.

AirBnb
Many airbnb rooms available in cities are apartments used just for airbnb and the host doesn't actually live there.
Sometimes the address and the owner's name are not reported to the post office by the host. When the address is not reported to the post office, they consider the place as a vacant house and would not deliver any items. Make sure if you use Aibnb, your host has reported the address to the post office.