Nice, but he had to make a large hole into his Alfa(?) to fit that thing inside. I would have used those small "vibration motors" for phones, they should have been the right size for the Alfa's Torpedo tubes.
こんにちは、 私は魚雷に関する記事を書いています。 私はあなたとyoutubeのリンクについて言及したいと思います。 これを行う許可がありますか? 平和、 トム Hello, I am writting an article about torpedoes. I would like to mention you and your youtube link. May I have your permission to do this? Peace, tom