noun
transformation belt; superhero belt
A belt that triggers a transformation, especially into a superhero form. Originated from the Kamen Rider TV series and now a common trope in tokusatsu and anime.
仮面ライダーは変身ベルトを使って変身する。
Kamen Rider transforms using a transformation belt.
この変身ベルトはおもちゃとしても人気
This transformation belt is also popular as a toy.