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    KitchenLunchboxesECOlunchbox Three-in-One Stainless Steel Bento Box
    #2 of 11
    ECOlunchbox Three-in-One Stainless Steel Bento Box

    Key Specs

    Body Material

    Gasket / Seal Material

    Leak-Proof

    Compartments

    ECOlunchbox

    ECOlunchbox Three-in-One Stainless Steel Bento Box

    #2 of 11 lunch boxs tested

    No sponsored placements·By Renée Torres
    8.6R3 Score / 10
    RecommendedA strong pick for most families.
    No sponsored placements· By Renée Torres

    The bottom line

    What the product listing won't tell you

    Know before you buy

    The Three-in-One is one of the simplest and least expensive all-metal, plastic-free lunch boxes available — but its press-fit nesting design makes it genuinely hard for young children to open independently, and it cannot hold any liquid.

    Buy it if
    • Your child is 6 or older and can pull apart nested metal containers without teacher help.

    ECOlunchbox Three-in-One Stainless Steel Bento Box

    ECOlunchbox

    ECOlunchbox Three-in-One Stainless Steel Bento Box

    $24.95
    See if it passed our safety test for freeBuy
    ECOlunchbox Three-in-One Stainless Steel Bento Box

    ECOlunchbox

    ECOlunchbox Three-in-One Stainless Steel Bento Box

    $24.95Buy on Amazon
    Safety
    Usability
    Efficacy
    Unlock safety scores for free

    $24.95

    Buy on Amazon

    We may earn a commission. It doesn't affect our scores.

  1. Their typical lunch is dry foods — sandwiches, cheese, crackers, grapes, carrots — with no sauces or wet items that need containment.

  2. You want all-stainless construction with zero plastic components and are comfortable with brand-declared (not lab-verified) safety claims.

  3. You want the easiest possible cleanup — three pieces, no disassembly, straight into the dishwasher.

  4. You're looking for an all-stainless lunch box at the lowest possible price point.

  5. Skip if
    • Your child is under 6 — the press-fit nesting design will require teacher help at lunch daily.

    • Their lunch regularly includes sauces, dressings, yogurt, or juicy fruits — this box will leak.

    • You require a published third-party food-contact safety certification — no LFGB, NSF, or independent lab test has been published for this product.

    • You want 304-grade (food-service standard) stainless, not 201-grade.

    What's inside

    Specs the product listing doesn't explain

    Safety & Materials

    What your food and family come into contact with every use

    Body MaterialGasket / Seal MaterialDishwasher SafeCertifications
    Efficacy

    What determines how well this performs its core job

    Total Capacity
    Usability

    Ease of use, maintenance, and longevity

    Leak-ProofCompartmentsClosure / Latch

    See exactly what's in this lunch box

    Free account unlocks full material breakdown, safety test results, and spec details.

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    How we scored it

    6 criteria - open any layer to see exactly what we found

    Safety

    Efficacy

    Usability

    Food Contact Material SafetyCritical

    “Is 201 stainless actually safe for my child's food every day?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Safety research

    Safety standards and ingredients related to ECOlunchbox Three-in-One Stainless Steel Bento Box

    Microplastics from Heated Plasticsingredients

    Microscopic plastic particles smaller than 5mm (microplastics) and smaller than 1 micrometer (nanoplastics) that shed from plastic components when repeatedly heated. Recent studies show heated plastics release millions of micro- and nanoplastic particles per gram. These particles have been found in human blood, placenta, and breast milk, and can carry other chemicals like phthalates and BPA as they leach into food and air.

    Melamineingredients

    An organic compound used to make hard, heat-resistant plastic (melamine resin). Found in cheap air fryer accessories, dishes, and utensils. Leaches formaldehyde when heated above 160 degrees F (70 degrees C). Not safe for high-heat cooking. Associated with kidney damage and the 2008 Chinese milk contamination scandal.

    Phthalatesingredients

    A group of plasticizer chemicals used to make plastics flexible and durable. Found in PVC, vinyl, food packaging, personal care products, and kitchen appliance components. Phthalates are endocrine disruptors that affect testosterone and thyroid hormones, with strong evidence linking them to reproductive harm, particularly in developing boys.

    Every term is independently researched and sourced.

    Full Safety Dictionary

    Where to buy

    Verified retailer - current pricing

    Starting price

    $24.95

    R3 approved retailer Score unaffected by purchase
    Buy on Amazon

    We earn a small commission on purchases. It never influences our scores - R3 is funded by readers, not brands.

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    #2 of 11 lunch boxs reviewed

    Did the ECOlunchbox Three-in-One Stainless Steel Bento Box pass our safety screen?

    Free account unlocks the full verdict, pillar scores, spec values, and which other lunch boxs made our list.

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    Empty Weight (all 3 pieces)
    Warranty
    Observed Price
    Body / Tray MaterialLid & Gasket / Seal MaterialChemical Safety Disclosure
    Third-Party Certification & VerificationCritical

    “Has anyone actually tested this box to confirm the materials are safe?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Third-Party Safety Certifications
    Seal & PortabilityCritical

    “Will this box make it to school without everything leaking and mixing?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Leak-Proof PerformanceCompartment Design & Capacity
    Child-FriendlinessImportant

    “Can my 6-year-old actually open this at lunch without a teacher's help?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Ease of Opening for ChildrenEmpty Weight
    Cleaning & MaintenanceImportant

    “How much time will I spend cleaning this every night?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Ease of CleaningStain & Odor Resistance
    Durability & LongevityImportant

    “Will this last the whole school year, or will I be replacing it by March?”

    ▾

    The scoring rationale is locked

    Free account unlocks exactly why this product scored the way it did.

    See the full scoring for free

    Criteria

    Material DurabilityWarranty Coverage