The Wostok Amphibia is a Russian diver watch created in 1967 for the USSR navy. The amphibia design was led by Wostok's chief of their new design bureau. The objectives were to create a watch that was competitive with contemporary dive watches such as the Blancpain 50 Fathoms, the Rolex Submariner, and the watches using the compressor case, and to create a watch that could operate reliably at the temperature and pressure of a depth of 200 meters (and later 300 meters). The chief designers were Mikhail Fedorovich Novikov and Vera Fedorovna Belov.

The Amphibia is the embodiment of possibly the most simple concept for creating a watertight case. The basic principle is to use the outside pressure to create the seal needed to prevent water from entering the case. The further the case sinks, the higher the outside pressure, the higher pressure is exerted on the case, creating a dynamically tighter seal. This is opposed to the idea where you create a case that creates the pressure to withstand 20ATM of pressure no matter what pressure it experiences (1 ATM at sealevel, for instance). This is a design similar to the western compressor case, a patent for which was filed at least as early as 1954, and granted in '56(US pat. 2,737,009). The advantage of the compression design is that you do not need to tighten any of the seals to a pressure that would withstand 20ATM, it also eliminates several pieces required to create such a seal.

The Amphibia's crystal is 3mm thick lucite(50% thicker than standard) that is ground like a precision lens to create a very good size and seal. The lucite deforms plastically by a half millimeter under pressure whereas the slightest deformation of a glass or sapphire crystal would crack it. This allows a much lighter, smaller, cheaper crystal to be used. It also does not require the extra rubber seals and a very high pressure crystal retaining ring.

While a traditional caseback gasket would experience sheer forces with the rotation of a screwback case used for a traditional hermetic case that would leave the gasket permanently compressed, making it unable to return to its original shape and unsuitable for reuse, the Amphibia uses a very wide sintered gasket. This solved a problem found during the design where when surfacing, the gasket which had been compressed by 20-30% decompressed slower than the pressure on the caseback, critically weakening the seal. To fix the problem of the O-Ring sheer, they used a bayonet mount held in place by a nut. This use of a very large gasket distributes the force of the pressure which can be a problem with O-rings.

The case is made of stainless steel. The thickness of the caseback is 1MM, double the regular thickness. The crown screws down with a gasket to prevent water from entering from the stem opening. The stem incorporates a clutch to protect it from lateral forces. This clutch gives the stem a wobbly feel as it doesn't engage unless you pull the crown away from the watch.

The watch includes a rotating bezel which is used to mark the time you first submersed. The dial and hands also have luminescent so that the watch can be read in the darkness of ocean depths.