The Ultimate Performance Crop is designed for high impact activities and does it all! Designed to hold a heart rate monitor and an MP3 player, the swivel front shoulder strap clasp will move and flex with your body, whether your running or kick boxing. This crop will reduce breast bounce by up to 60%, while providing you with breathability and reducing chafing, thanks to the seamfree, perforated contour cups and racer back clip and hook adjustment allowing for multiple strap positions. The crop also reduces irritation in high rub areas with its moisture wicking padded shoulder straps, underbust and body band.