You'll need a plastic mold. You can either use a novelty ice cube tray or small ice cream molds, or you can also use used plastic jello or pudding cups.

你需要一个塑料模具，可以是一个造型新颖的冰格盘，或者小的冰淇淋模具，你还可以选用塑料果冻杯或者布丁杯。

youdao

The collector basically looks like a tennis racket filled with ice cubes, so this is kind of like a big ice-cube tray, and each ice cube is not made out of ice, but it's made out of this aerogel.

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