From the Official Beach Volleyball Rules Particular important are the 7cm max for bikini sides and design has to be with'open upper chest' 24.4 Women?s Uniforms ? Style (see diagram) The top must fit closely to the body and the design must be with deep cutaway armholes on the back, upper chest and stomach (2-piece), respecting the space for the required for the manufacturer logo, player number, country flag and country code, and the place for the player?s name. The briefs should be in accordance with the enclosed diagram, be a close fit and be cut on an upward angle towards the top of the leg. The side width must be maximum 7 cm. The one piece uniform must closely fit and the design must be with open back and upper chest, respecting the space for the required inscriptions to be made. ? Fabric The top and briefs or the one piece uniform must be made of elastic material, Lycra or a combination of Lycra/cotton, or other similar quality synthetic material.