Sparx Mens Premium Triathlon Suit Padded Triathlon Tri Suit Race Suit Swim Bike Run

My husband swims in open water and he like to swim for a longer distance, is that can make him float to to catch his breath and then keep going ?

I am 6’3 and about 175 lbs make. Skinny athletic build. What size should I go with?

Is this a one or two piece suit?

I am trying to size this out, but my measurements are making it sound like i'll need a xxx. i am 6'1", 235 with a 47" chest and 38" waist. 3x really?