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Weck Mold Jar 743 with Glass Lid (3/4 Liter)

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Weck

Weck

Mold Jar 743 with Glass Lid, Rubber Ring, and Steel Clamps (3/4 liter)

Glass, glass, natural rubber, steel. Verified fully plastic-free from Weck primary sources; the benchmark closure for plastic-free food preservation.

1 / 10 Low plastic footprint $
Verified plastic-free

The German canning classic: a thick glass jar sealed by a glass lid, a rubber gasket, and stainless steel clamps. No plastic anywhere in the closure, which makes it one of the only fully plastic-free canning systems.

How this score breaks down

Plastic in the product and its packaging Little plastic
Thick tempered glass jar and glass lid, sealed with a natural rubber gasket and stainless steel clamps. Weck confirms on its own site that the rings are made of natural rubber. BPA-free, dishwasher and microwave safe glass per the listing.
Microplastic shedding and leaching Doesn't shed
None expected. Food touches glass and the rubber gasket only; the closure contains no plastic parts.
End of life: persistence and recovery Recovers well
Recyclable, repairable, or genuinely recovered; low persistence.
Plastic-derived chemicals of concern No leaching concern
No PFAS, PTFE, BPA, or other leaching plastics in food or heat contact.
Transparency and verification Mostly disclosed
How fully the brand discloses its materials and coatings, and whether independent testing backs it up.

Strengths

  • Glass lid instead of a plastic or plastisol-lined metal lid
  • Fully repairable system: rings, clips, and lids all sold as spares
  • Endlessly reusable and recyclable glass and steel
  • Century-old design with no plastic era compromises

Trade-offs

  • Natural rubber rings stretch if exposed to oils and need occasional replacement (cheap and sold in bags)
  • Glass lids can chip if dropped; spare parts fix it
  • Sold on Amazon via a third-party reseller

What's inside

Thick tempered glass jar and glass lid, sealed with a natural rubber gasket and stainless steel clamps. Weck confirms on its own site that the rings are made of natural rubber. BPA-free, dishwasher and microwave safe glass per the listing.

Free of Plastic lid, plastic seal, plastic clamp

Packaging
Not stated
Microplastics
None expected. Food touches glass and the rubber gasket only; the closure contains no plastic parts.

Attributes

What this product is, at a glance.

Plastic-Free ProductNatural Rubber SealReusableDishwasher SafeReplacement Parts Available

Certifications

None listed. We only show independent third-party certifications we can verify with the issuing body, and this product does not currently hold any.

About Weck

Weck has made home-canning glass in Germany for over a century, and its glass-lid-and-rubber-ring system predates the plastic era entirely. The 743 mold jar is the versatile 3/4 liter workhorse of the range.

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Melissa Walker, founder of Thriving Sustainably

Hi, I’m Melissa-founder of Thriving Sustainably

Melissa Walker is the founder of Thriving Sustainably. A mom who started reading the labels after learning how much microplastic ends up in our bodies, she co-leads the environmental pillar of a Fortune 500 company’s employee sustainability program and rates brands against public certification databases so families can lower their microplastic exposure without the guesswork.