Oxygen wafer

Oxygen wafers are a recent invention of robotics expert Isaac Sumdac. Resembling small paper discs, they can be sucked on to release oxygen directly into the blood, thereby relieving the need to breathe and allowing humans to dive underwater without bulky scuba gear.

Fiction

Web of Deception

When you and Sari needed to dive down to the Autobot ship at the bottom of Lake Erie, Sari produced two oxygen wafers. The wafers lasted long enough for them to swim down to the ship, along with Prowl and Bumblebee, the latter of whom could have simply transformed and carried them down there. Web of Deception