It should fit snug, yet comfortably for kids to have full range of motion while swimming. The one shown in the video is a size medium/large, designed to fit children 3-4 years old from 26-40 lbs. A small/medium size is also available for 2-3 year olds.
Disney Princess Swimming Adventures Ariel
Deluxe Beach Bag
from American Plastic Toys Inc.
Summer Showers Splash Tower Water Table
PJ Masks Water Rescue Packs
from Little Kids, Inc.
Robo Alive Junior Little Fish
Dragons Drago's Ship
Cute Lil' Pups Swim to Me Puppy
from MGA Entertainment
E Lite Beach Blanket Pool