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. Berlei is the only sports bra brand tested, approved and endorsed by the Australian Institute of Sport. Cross-back functionality for additional support and flexibility during movement. Wide adjustable straps help to stabilise and minimise bounce. Mesh panelling increases breathability. Adjustable hook and eye.