The Protei-5 is a small Russian one-man diver-carrying vehicle intended for use by commando frogmen such as those in the Spetsnaz. It is battery electric powered. The batteries are an expensive type that contain silver. It clips on under the diver with a clip over each shoulder and one between his legs. Its casing is aluminium. It was intended to be clipped onto the outside of a submarine; near the operation site the frogmen would airlock out underwater and unhitch their Protei 5's and ride them to the operation site.
The rod sticking out of the front end was meant to carry a lamp.
The lever on the left bow is the motor's on/off switch. There is no speed control.
The frogman steers by moving his legs about.
See Diver Dave's Site for more pictures and a longer description.
Only one Protei-5 has found its way out of the ex-USSR, as far as is known.
There have been similar designs made in Russia. For an account of diving with them, see Afonchenko.
That page is in Russian, and the images will need to be brightened to show details. There is an auto-translater at Babelfish. To get a translation, select with the mouse and copy-and-paste the whole page into Babelfish: if you tell Babelfish to read from that page's address, it will foul up on the many HTML formatting instructions in the page.
Protei is a Russian version of the classical Latin / Greek mythological name Proteus.