Peekaboo Seal Baby Romper
Peekaboo, I see you!
This adorable animal-themed onesie brings a splash of fun with its 3D puffy fins and a playful tail that wiggles along—just like a cheeky seal ready for a game of peekaboo! The interactive design encourages tiny hands to play, touch, and discover.
Crafted from premium milky cotton, it’s cooling, ultra-soft, breathable, and gentle on delicate skin—perfect for all-day comfort. Snap buttons at the shoulder and crotch make dressing and diaper changes a breeze.
Available in sizes 0 to 24 months, with a matching tee for older kids—perfect for twinning, playdates, and sibling bonding!
| Size reference: | |||
| Size | Length | Shoulder | Chest |
| 60 (0-6M) | 42cm | 23cm | 28cm |
| 70 (6-12M) | 45cm | 24cm | 30cm |
| 80 (12-24M) | 48cm | 25cm | 32cm |
| *All dimensions are measured lying flat. | |||
Size Guide
| mimi mono Size | Age | Height (cm) | Weight (kg) | EUR Size | US Size |
| 60 | 0-6 months | 50-60 | 4-7 | Newborn–3M | Newborn–3M |
| 70 | 6-12 months | 60-70 | 7-9 | 3-6M | 3-6M |
| 80 | 12-18 months | 70-80 | 9-11 | 6-12M | 6-12M |
| 90 | 18-24 months | 80-90 | 11-13 | 12-18M | 12-18M |
| 100 | 2-3 years | 90-100 | 13-15 | 2-3Y | 2T-3T |
| 110 | 4-5 years | 100-110 | 15-18 | 4-5Y | 4T-5T |
| 120 | 6-7 years | 110-120 | 18-20 | 6-7Y | 6-7 |
| 130 | 7-8 years | 120-130 | 20-25 | 7-8Y | 7-8 |
| 140 | 9-10 years | 130-140 | 25-35 | 9-10Y | 10 |
| 150 | 10-12 years | 140-150 | 35-45 | 11-13Y | 12-14 |
| 160 | 12 years - Adult (Unisex) | 150-160 | 45-55 | Teen/XS | US 0-2 |
| S | Adult (Unisex) | - | - | EUR 32-34 | US 4-6 |
| M | Adult (Unisex) | - | - | EUR 36-38 | US 8-10 |
| L | Adult (Unisex) | - | - | EUR 40-42 | US 10-12 |
Shipping Rates
👋 We ship worldwide!
[IMPORTANT NOTE: Import taxes and customs fees are not included in the final payment for all orders outside of Japan.]
Shipping rates within Japan
A flat shipping fee of ¥500 will be applied per local order.
Do you ship internationally?
Yes. Shipping costs are auto-calculated by weight and shown at checkout. Import taxes and customs fees are excluded; the delivery service company will contact you for these payments separately. Check your country’s import tax rates before ordering.
When will my purchase ship?
In-stock items typically ship out within 3-5 business days after the order is placed. Pre-orders ship once they arrive; check each pre-order product page for estimated arrival dates.
How long will my parcel take to arrive?
Delivery duration is between 3-7 business days, depending on your location.
How can I track my order?
You’ll get an email with tracking information as soon as your order ships.
Check out our exchange policy here.
Exchange & Returns
What's your exchange policy?
We accept exchanges for unworn, unwashed items within 7 days upon receiving your parcel. This applies to regular-priced items only. Customers will be liable for shipping and handling costs unless the exchange is due to manufacturing defects. Sale items, discount code orders, and accessories are non-exchangeable.
How do I request an exchange?
Contact us at contact@mimimono.com for assistance.
Do you accept refunds?
We do not accept refunds due to hygiene reasons, unless it is on a case by case basis.
We ship worldwide. Check our shipping rates here.
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