有不同形状浮体可选择：水滴形（不倒翁形）在急流中更稳定；

Supply many different patterns : water drop shape(tumbler shape)is most steady in torrent;

youdao

有不同形状浮体可选择：水滴形（不倒翁形）在急流中更稳定；

Supply many different patterns : water drop shape(tumbler shape)is most steady in torrent;

youdao