This is a short custom experimental video. Xiaoyu was lying prone and wearing a Japanese one-piece school swimsuit and freediving gear: a vintage oval mask, a snorkel and fins. The mouthpiece of the snorkel was fixed to her mouth by bondage tape, so that she can only breathe through the snorkel. Then I use black electrical tape to seal the opening of the snorkel to push Xiaoyu to practice breath hold. Her hands were bound behind her back by bondage tape in the second half of the video. Listen to her beautiful breath sounds!