They are thinner than what is typically sold online. All I know is that multiple onigiri stores apparently get it from the same place in Kappabashi. Onigiri Bongo mentioned that they get their polyethylene onigiri molds from the same place that Bonta Bonta does. It originally started out as a custom order just for Bonta Bonta and then restaurants like Onigiri Bongo and Risaku requested the same ones. My guess is Majimaya which sells a lot of custom molds although they mostly do it for confectionery so not sure if they would have got it from there. For reference, [here are how the molds look like.](https://www.youtube.com/watch?v=Vzy1n9m2N7s&list=TLGG4PeRJyDnDqsyNTAyMjAyNA&t=1s) Any idea which store it could be?
by Shota_Kazehaya