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Curated by parents and pediatricians

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Authentic Imports

Directly from trusted Korean makers

Leak Proof Sips, Happy Moments.

Korea’s No.1 Toddler Straw Cup

946,000+

Cups sold annually

30+ Countries

Loved by Moms Worldwide

Patented tech

related to straw nipples

CPSIA Compliant

Tested by a CPSC - verified Laboratories

Onzenna

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.

One 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-dust

Sealed 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

One of the Top 5 Best-Selling Toddler Straw Cup Brands on Amazon US
#1 Best-Selling PPSU Straw Cup

Over 8,000 reviews ★ 4.5 out of 5.0 rating

Stainless Steel

Stainless Steel is a high-performance material known for its exceptional durability and resistance to rust and corrosion. Commonly used in medical, food, and industrial applications, it is a safe and hygienic choice for various products. Stainless Steel is perfect for baby bottles, cups, and kitchenware as it does not absorb odor or color and maintains its quality even after repeated sterilization. Unlike plastic, it is unbreakable and highly resistant to temperature changes, ensuring long-lasting use. There is no better choice. Now, stainless steel products come in various finishes, from classic silver to modern matte black, offering both style and functionality. Try Grosmimi Stainless Steel.

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.

  • SUS304/316

    Medical and food-grade stainless steel

  • BPAFree

    No plastic contact with the liquid

  • 🇰🇷

    Made in Korea by Grosmimi

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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 product

When 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.

img-onz-vine-grosmimi-key04-progression.webp

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.

You're starting with: Flip Top Cup (12 Months+)

What's Included

Everything in the box

  • Cup Body

    PPSU or Stainless Steel

  • Flip Top Cap

    One-touch open

  • Silicone Straw Teat

    Included

  • Silicone Straw Tube

    Replaceable

Includes Straw teat. Additional straw teats and accessories are available separately.

Care & Sterilization

How to sterilize each part

MethodBody (SUS 304)Cap (PP)Straw (Silicone)Accessories
Hot Water Yes Yes Yes Yes
UV Sterilizer Yes Yes No Yes
Dishwasher Yes Yes No Yes
Steam Yes Yes Yes Yes
Microwave No No No No

Tips: Do NOT microwave stainless steel. Replace silicone parts every 2-3 months. Always disassemble all parts before cleaning.

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.

  • img-onz-vine-grosmimi-award-badge.jpg

    Korean Brand Consumer Evaluation 2023

    Infant Products Winner — Feeding Bottle & Straw Cup category.

Replacement

  • Weighted Spout kit

    • Age: +6m
    • Strength: Soft
    • Durability: Weak
    Shop Now
  • Weighted Straw kit

    • Age: +6m
    • Strength: Soft
    • Durability: Weak
    Shop Now
  • Straw Kit Stage 1

    • Age: +6m
    • Strength: Soft
    • Durability: Weak
    Shop Now
  • Straw Kit Stage 2

    • Age: +12m
    • Strength: Hard
    • Durability: Strong
    Shop Now
  • Stage2 Nipple only

    • Age: +12m
    • Strength: Hard
    • Durability: Strong
    Shop Now

We're answerable!

4.9
Rated 4.9 out of 5 stars
Based on 31 reviews
Total 5 star reviews: 29 Total 4 star reviews: 2 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend this product
31 reviews
  • CM
    Codruta M.
    Verified Buyer
    Reviewing
    Grosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
    I recommend this product
    Baby's Age 6 Months - 2 Years
    Baby's Height 26.5 Inches to 31.5 Inches
    Rated 5 out of 5 stars
    2 weeks ago
    Love this bottle!!!

    Such a cute bottle and love that is stainless steel 😍 my baby refuses any type of bottles ( breastfed baby haha) but actually loves this one which did surprise me!!!

  • IN
    Iris N.
    Verified Buyer
    Reviewing
    Grosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
    I recommend this product
    Baby's Age 6 Months - 2 Years
    Rated 5 out of 5 stars
    4 weeks ago
    great cup for my one year old!

    nice that it is spill proof as well as stainless steel.

  • DY Profile picture for Donald Y.
    Donald Y.
    Verified Buyer
    Reviewing
    Grosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
    I recommend this product
    Baby's Age 6 Months - 2 Years
    Baby's Height 26.5 Inches to 31.5 Inches
    Rated 5 out of 5 stars
    1 month ago
    Love this!!

    Fits in my bottle washer. Amazing.

  • KA
    Krista A.
    Verified Buyer
    Reviewing
    Grosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
    I recommend this product
    Baby's Age 2 Years - 8 Years
    Baby's Height 36.5 Inches to 42.5 Inches
    Rated 5 out of 5 stars
    4 months ago
    Must buy!

    My son loves this cup and I love that it’s spill proof! Highly recommend!!

  • AH
    Asena H.
    Verified Buyer
    Reviewing
    Grosmimi Stainless Steel Straw Cup with Flip Top - 10oz (12 Months+)
    I recommend this product
    Baby's Age 2 Years - 8 Years
    Rated 5 out of 5 stars
    5 months ago
    so cute and functional

    love this so cute and functional my daughter obsessed