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№ 1 Hydrogen Romper

№ 1 Hydrogen Romper


To pay homage to the building blocks of all matter and Dmitri Mendeleev’s masterpiece, The Periodic Table of Elements, Theory Tot presents our Elements collection.

Hydrogen is the first of the elements, it's the lightest and most abundant element in our Universe! First discovered in 1766 by Henry Cavendish.

This cute elemental number is the perfect attire for the up-and-coming tiny scientist, it’s soft and comfortable, but durable enough to withstand any scientific expedition, no matter how messy.

These rompers are designed with parents in mind with an easy on-and-off neckband for speedy outfit changes and snaps for easy diaper change access or quick opening for toddlers that need to go NOW!

Each design is printed using eco-friendly water based inks onto rompers made in the USA, sweatshop free, by American Apparel. The placement of the graphic will vary depending on the romper size you order.



Fabric 100% fine ring-spun combed organic cotton
Shrinkage will shrink an average of one size when put in the dryer
Gender neutral

Baby Size Chart

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