Niko-nui Keychains Onigiri (Rice Balls) A cute set featuring an umeboshi (pickled plum) onigiri and tempura onigiri. Magnets are embedded in each end, allowing them to stick together when brought close. The magnetic force is weak, so they attach loosely. I purchased them at a nearby shopping center. The onigiri seem to be popular, and some online shops are out of stock. If anyone is looking for them, please feel free. They will be sent in simple packaging.