MKRQuick Drying Breathable Cooling Short Sleeve Sports T-Shirt with UPF40+ Sun UV Protection

Is there a size chart?

What size chest in the medium?

Would this this top be suitable to put over swimsuit to go in a pool?

i have just received ny t shirt ordered large but the size is very generous , i think the large must be a 44in chest , i will need to order medium whi