This 3D print model of a submarine drone chassis has been designed for use low pressure waters less than 50cm below surface, it features a motor box for dorsal fins and caudal fins(joined to its main chassis using a pipe connector for waterproofing), this motor box houses motors with 20rpm for smooth descent, ascent and steering of this drone, it has a space for a darwin hulk AIO FC in its caudal motor box and a chamber for a darwin water proof camera and a lumen LED in its top periscope. It houses a HRB 1600mAh 6s battery (also joined using a pipe connector) below its belly in a waterproof chamber and a lumen LED facing its dorsal fin to avoid collision when diving. It also has a screw holes for a subsea light below its top LED to ensure its camera can see clearly when diving. Its caudal fin is designed for steering and can support underwater thrusters while its dorsal fin is designed for ascent and descent.
Disclaimer: do not buy this 3D print model if you cannot redesign it in a design software to join its bottom LED cover with its battery bottom cover, design well articulated and fitting grooves in cylinders that have been designed to run each other, design 6 2mm screws for a subsea light and dorsal fin, design a 5mm screw for a caudal fin, design four 6 mm screws for a battery cover.