Showa
The Showa era shelf runs to 1989, from Giant Robo to Kamen Rider Black RX.
Heisei
The Heisei era shelf runs from 1989 to 2019, from Chikyuu Sentai Fiveman to Kishiryu Sentai Ryusoulger.
Reiwa
The Reiwa era shelf gathers the newest heroes, from Mashin Sentai Kiramager to Ultraman Omega.