Stainless Steel Straw Cup
GrosmimiGrosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
Free shipping on orders $50+ · Ships in 1-3 business days
Quantity
About This Item
- Made with Stainless Steel
- The newest version features great improvements in coating, design, and the addition of a flip-top
- Stage 2 Straw kit is included - Vacuum Insulated: Keeps beverages hot and cold up to 6 hours
Why Grosmimi?
6 reasons parents choose this cup
Stainless Steel Body
SUS 304/316 stainless steel keeps drinks at the right temperature. Durable, hygienic, and taste-neutral.
One-Touch Flip Top
Opens with a single press for easy on-the-go drinking. Locks shut securely.
Soft Liquid Silicone
Softness and smoothness of the straw protect baby's teeth and gums.
Leak-Proof '+Cut' Straw Design
The + cut prevents leaks even when the cup is upside down.
Easy to Clean
Wide-neck design makes the cup easy to wash and assemble.
Made in Korea
Manufactured by Grosmimi in Korea.
Leak-Proof Design
Squeeze it. Pinch it. It won't leak.
The + cut straw tip seals under pressure. Toss it in the diaper bag — no spills, no mess.
✓ + Cut seals under pressure. No extra valves.Durable PPSU
Babies drop things. This cup handles it.
FDA compliant PPSU is incredibly durable — used for medical devices that get sterilized over and over.
✓ Incredibly durable FDA-compliant PPSUOne Touch Cap
Open with one hand. While holding baby with the other.
Thumb-press flip cap opens instantly. Steel-free, anti-dust design keeps the straw clean between sips.
✓ One Touch Cap — steel-free, anti-dust360° Rotating Handles
Grip from any direction. No wrong way to hold it.
Handles rotate freely so small hands can grip from any angle.
✓ 360° rotating — grip from any directionSealed in Motion
Shake it. Swing it. Still sealed.
Toddlers don't just drink — they shake, throw, and swing. The + cut straw stays sealed through all of it.
✓ + Cut stays sealed during motion
Selection Guide
Start small, then size up.
The 200ml flip top is lighter and easier for toddlers to carry. The 300ml is ideal for longer outings or when your child drinks more volume.
200ml
Compact, lighter, easier to hold
300ml
More volume for bigger appetites
← This productWhen babies start teething, they begin to chew on the straw teat. For babies over 12 months who tend to bite, a firmer straw teat is available separately.
What's Included
Everything in the box
Includes Straw teat. Additional straw teats and accessories are available separately.
Cup Body
PPSU or Stainless Steel
Flip Top Cap
One-touch open
Silicone Straw Teat
Included
Silicone Straw Tube
Replaceable
Weighted Straw Kit
Any-angle drinking
Grows With Your Baby
One system, every stage.
Grosmimi's full product line covers every stage — from bottle to straw cup to tumbler. Each product is compatible with the same accessories, so you invest in a system, not throwaway cups.
The Brand
From Grosmimi. Made in Korea.
Grosmimi crafts PPSU feeding products for babies — from bottles to straw cups to tumblers. Made in Korea, trusted by parents worldwide.
Korean Brand Consumer Evaluation 2023
Infant Products Winner — Feeding Bottle & Straw Cup category.
The Material
Why Stainless Steel.
SUS 304 and SUS 316 stainless steel are the same grades used in medical equipment and food processing. They resist corrosion, retain no flavors, and keep drinks at the right temperature for hours — without any plastic touching the liquid.
SUS 304/316
Medical and food-grade stainless steel
BPA Free
No plastic contact with the liquid
🇰🇷
Made in Korea by Grosmimi
What Parents Say
What parents are saying
“My daughter finally drinks water on her own. The weighted straw was the game changer.”
Sarah M.
Baby: 9mo · Verified
“Switched after reading about microplastics. The PPSU difference is real — doesn't discolor after months.”
Jennifer K.
Baby: 14mo · Verified
“We're on our third Grosmimi — 6oz, 10oz, now the tumbler. Best cups ever. Zero leaks.”
David L.
Toddler: 2.5yr · Repeat buyer
Care & Sterilization
How to sterilize each part
| Method | Body (SUS 304) | Cap (PP) | Straw (Silicone) | Accessories |
|---|---|---|---|---|
| Hot Water | ✓ | ✓ | ✓ | ✓ |
| UV Sterilizer | ✓ | ✓ | ✗ | ✓ |
| Dishwasher | ✓ | ✓ | ✗ | ✓ |
| Steam | ✓ | ✓ | ✓ | ✓ |
| Microwave | ✗ | ✗ | ✗ | ✗ |
Tips: Do NOT microwave stainless steel. Replace silicone parts every 2-3 months. Always disassemble all parts before cleaning.
Certifications
Certified safe
BPA Free
No plastic contact with the liquid
SUS 304/316
Medical and food-grade stainless steel
Made in Korea
Manufactured by Grosmimi in Korea
Disinfection Safe
Hot water, UV cabinet, and steam safe
Policies
Shipping & Returns
Shipping
- Free shipping on orders over $50
- Standard shipping: $5.99
- Ships within 1-3 business days
- Delivery: 5-10 business days
Returns
- 30-day return policy
- Items must be unused and unopened
- Contact hello@onzenna.com to start
- Full refund to original payment
FAQ
Frequently Asked Questions
Read
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Reviews
What Parents Are Saying
Based on 42 reviews
would recommend
this product
Customer Photos
See it in real homes· 2 photos
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Sign In to Write a Review42 reviews
Asena H.
so cute and functional
love this so cute and functional my daughter obsessed
Kamal
I love it
BriAnn B.
Spill proof cup
I have been through all the straw cups for my 2 toddlers to drink from that do not leak. I have tested this one and it’s the first to actually not leak. Love it and highly recommend!
Sarah S.
great, but expensive and loud when dropped
also a bit heavy for infants to hold
Katie
These are the best bottles! We had a couple of other brands when our LO was a little smaller but had we known about these, I would have started with them from the start with the smaller size since they're dishwasher safe.
