Three-bolts equipment
From Wikipedia, the free encyclopedia
Three-bolts equipment, (Tryok'h'boltovoye snaryajzeniye, Трехболтовое снаряжение, трехболтовка) is a kind of a standard diving dress which was used by the Russian Navy in 19th and 20th centuries. This standard diving dress consists of an air-supplied metallic helmet that is strapped with water-protected suit by three bolts.


