Swimming floats

Hi everyone, what are people doing for swimming aids? My LO has been going swimming since she was 12 weeks old so is very confident in the water and doesn't want to be held any more really. All of the arm bands I see, she doesn't weigh enough for. 11.3KG and some of the other floats wouldn't keep her fully supported. She doesn't like the ones you sit in as she cant splash and move as freely.