Mizugumo

Mizugumo, or water spider, consisted of five air bladders made of animal hide and pine resin and strung together. To use a mizugumo as a flotation device, the shinobi placed it on the water's surface underneath their torso and paddled with their arms and legs. The item's name came from the shinobi's appearance while using it: the shinobi skated along the water's surface like the Rokugani fishing spider.