The MK II Paradive Type XIII is based on the TR-50717 ("Paradive, Class B") platform, the Tornek-Rayville Division's evolution of the military watch specification MIL-W-50717. The Type XIII is the result of a mandate to develop a civilian version of the TR-50717 for the consumer and export market. In many ways the Type XIII is a nod to Mk II’s early days pushing forward the nascent watch modifications market and leading its design influences.
The dial design is lifted from the early Mk II archives using luminous markers to break up the dial into 15 minute quadrants. The date window has been moved to an auxiliary position at 4.30 to preserve all of the lume markers on the dial. The new Type XIII hands were developed through Mk II’s R&D dept with feedback from the Service department. The hands are a modernized 60s design that has been adapted to the use of SuperLumiNova. In order to adjust for the use of light charged luminous material the hour hand features a larger luminous filled area. The color scheme of the hands make use of negative space in order to emphasize the minute hands, subordinate the hour hand, while maintaining rigidity in the hand structure, making them less susceptible to warping due to vibration. (This last detail was based on a custom Blackwater series watch [aka Gen 1 Paradive] received for routine servicing where the Ploprof style hour hand had begun to develop an upward curvature as a result of vibration the watch experienced while the customer was deployed to Iraq.) The sweep is painted black/orange consistent with the desire for more negative space to improve readability and to enable quick reference.The TR-50717 Paradive case body platform re-engineered the MIL-W-507171 specification to enhance and extend performance in challenging environments. The Paradive utilizes a proven 3 piece construction. The screw back case enables the watch to use a solid one-piece stem, carries forward the ergonomic curved case back, and improves ease of maintenance. The crystal is press fit into the front of the case and made of a tougher synthetic sapphire material that will not develop the "crazing" endemic to the monocoque construction. A unidirectional 120-click bezel, a safety feature for underwater timing, replaces the bi-directional friction bezel. The bezel is also available with either diver's time elapse or 12-hr GMT inlays in aluminum.
Other notable changes and improvements include the replacement of fixed bars with reinforced heavy duty 2.50 mm spring bars that meet the ISO standards for dive watches. Each unit is also supplied with a thinner set of 1.80 mm spring bars for standard straps. This watch leverages a proprietary non-radioactive luminous material. The Japanese made NE15C movement delivers a longer power reserve and comparable accuracy to the reference mil-spec.