Seafolly's twist singlet. This is a very popular singlet as it has all the right features. Ruching through the front panel, internal soft cups, two shoulder straps and a twist through the bust for extra support. 

+ Swimwear features ruched torso and convertible straps
+ Soft cups and gripper tape for shape and support
+ Suitable for A-B cup and C cup
+ Fabric: (meryl) nylon / elastane / polyester mix

Fit can be on the small side, so worth trying a size up!