education.decodee on Instagram: "- The post showcases a 56-second video of the Seabike, a French-made handheld device where users pedal with their hands to drive twin propellers, enabling slow underwater propulsion at nominal speeds of 3.6 km/h and up to 7.9 km/h maximum, as per manufacturer specs. - Garnering 10.8 million views and 77k likes since August 19, 2025, it highlights the device's portability for snorkeling without scuba gear, though replies predominantly mock its glacial pace compare