This upper top clasps under the bra, gives you an extra boost in the chest, provides compression for body shaping without flattening your breast.
This underwear with elastic lace sleeve closure keep it from rolling up, compress saggy skin/bat wings, reduce upper arms size to make you look slimmer.
With three quarters sleeves covering the elbows, to some extend you can get some relief from arthritis or muscle strain/soreness after intensive fitness activities.