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Size Chart Adult Onesies
Have a good look at the size chart below to determine the right size for you.PLEASE NOTE: OppoSuits have a slim-fit design. When in doubt between two sizes, we recommend you to pick the larger size of the two.

HOW TO MEASURE
Grab a tape measure, write down the measurements and compare with our size chart for the right size.
Hold the tape horizontally to measure:
Hold the tape vertically to measure
Game night, lazy Sunday, costume party, or just a serious need for comfort? The Mario Onesie is your all-in-one power-up. Inspired by the world’s most iconic plumber, this onesie lets you jump straight into fun, nostalgia, and next-level coziness, no cheat codes required.
The Mario Onesie instantly transforms you into a recognizable gaming legend. The bold colors, playful details, and character hood make sure everyone knows exactly who you are. Whether you’re walking into a party or relaxing at home, this onesie delivers instant character and confidence.
Comfort is key, especially if you plan on wearing it for hours. The Mario Onesie is made from soft, cozy fabric with a relaxed fit that gives you full freedom to move. Sitting, lounging, celebrating, or dancing through the night? No problem. The front zipper makes it easy to suit up or power down whenever you want.
Picture this:
• A costume party where you want instant recognition
• A gaming night that turns into an all-nighter
• A themed event where fun matters more than formality
• A gift that guarantees a smile before it’s even unwrapped
That’s where the Mario Onesie wins every time.
• Instantly recognizable Mario-inspired design
• Soft, warm, and comfortable fabric
• Easy zip closure for everyday wear
• Perfect mix of nostalgia, fun, and comfort
Once you put on the Mario Onesie, you won’t want to take it off. It’s bold, playful, and ridiculously comfortable, everything you want in a standout outfit. Ready to level up your loungewear? Let’s-a go.
You are currently shipping to United States and your order will be billed in USD $.