If you're looking for a 1 piece snowsuit for a baby 12 months and over, then the Mossi Pink Snowsuit is a good bet. It's water resistant and well insulated with a quilted polyester lining that protects the snowsuit. I love the fact that there are 2 front zippers which make it easier to get on and off. It comes with a cute bunny motif on the front.
As you shop for a winter coat or snowsuit for baby, test the closures on the coats you're considering to be sure you can get the coat on and off of your baby easily. Remember that you may also be wearing winter gloves that make small zipper pulls hard to grasp. For toddlers, look for a coat or snowsuit with a closure that's easy for little fingers to master. Give zipper pulls and drawstrings a tug to be sure they are firmly attached.