Berlei Support Factor 4 - Extreme Impact. Reduces breast bounce by up to 60%. Your perfect bra for extreme impact sports such as running, kick boxing and HIIT. Engineered with the latest Berlei innovation to provide extreme support in an underwire bra. Contour cups provide breathability and reduce chafing. Racer back clip and hook adjustment designed to allow for multiple shoulder strap positions. Moisture wicking padded shoulder straps, underbust and body band minimises irritation in high rub areas. Nylon / Elastane.