What protective underwater clothing did Leonardo da Vinci sketch for divers?

Leonardo da Vinci sketched a diving suit for underwater operations. His design included a full-body covering, a breathing arrangement, and equipment intended to let a diver remain below the surface.

The concept appears in Leonardo’s early sixteenth-century studies of military engineering. It was associated with plans for divers to approach enemy ships underwater and damage them, although there is no reliable evidence that Leonardo’s complete suit was built or used in warfare.

Leonardo’s notes show awareness that a diver needed both protection and a way to obtain air. Some reconstructions associate his design with a breathing tube connected to the surface, while other elements include a mask, gloves, and a method of carrying air.

The design predates modern scuba equipment by centuries. It should not be called a wetsuit: wetsuits primarily conserve body heat, whereas Leonardo’s proposal focused on underwater breathing and operational concealment.