<P> A "shortie" wetsuit may be worn over a full wetsuit for added warmth . Some vendors sell a very similar item and refer to it as a' core warmer' when worn over another wetsuit . A "skin" may also be worn under a wetsuit . This practice started with divers (of both sexes) wearing body tights under a wetsuit for extra warmth and to make donning and removing the wetsuit easier . A "skin" may also be as an undersuit beneath a drysuit in temperatures where a full undersuit is not necessary . </P> <P> An atmospheric diving suit is a small one - man articulated submersible of anthropomorphic form which resembles a suit of armour, with elaborate pressure joints to allow articulation while maintaining an internal pressure of one atmosphere . </P> <P> These can be used for very deep dives for long periods without the need for decompression, and eliminate the majority of physiological dangers associated with deep diving . Divers do not even need to be skilled swimmers . Mobility and dexterity are usually restricted by mechanical constraints, and the ergonomics of movement are problematic . </P>

Why divers have to wear special suits before diving into a deep sea
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