These are images of the owner certificate, the owner card, and the memorial folder, which are sent to those who donate over ¥10,000 for the Castle Restoration Fund.
The main photo is the owner certificate.

Janome-mon (right)- the family crest of Kato Kiyomasa, who built the castle
Kuyo-mon (left) – the family crest of the Hosokawa family
The gold logo is the symbol of Kumamoto City.
写真トップは１００００円以上の寄付をした人に送られる城主証。　　　　　　　　　　　右が加藤の蛇の目紋、左が細川家の九曜紋。金色は熊本市章。

The owner card makes your admission free at tourism spots run by Kumamoto City. It also gives you a variety of services at affiliated shops and restaurants.
城主手形（名刺サイズ）があると熊本市の観光施設及び記念館に無料入場できる他、協賛店で様々なサービスが受けられます。

http://wakuwaku-kumamoto.com/info/jyousyu3.php
The folder designed by cartoonist Eiichiro Oda from Kumamoto, who is famous for his “One Piece”.
熊本出身の漫画家　尾田栄一郎さんによる「ワンピース」とのコラボ　クリアファイル。

Credit cards (VISA, Master, JCB, and American Express) as well as T-Points can be used for donations!
If a donor is living in Japan, an “owner” certificate will be delivered in 4 months, and the donor’s name will be shown on a special screen at Josai-en within 3 months.