These German-made Weck Jars are formed from thick, hardy glass and made to withstand boiling, sterilizing and indefinite repeated use. The glass lids fit snugly on the jar with a natural rubber ring creating a hermetic seal. The lid is held in place with two stainless steel spring clamps, adjusted for permanent spring action even with continual use.
The system design is ingenious. When the seal on the jar is intact and airtight, the tab on the rubber ring will face downwards. The clamps can then be removed and reused. The jars are stackable for easy storage. And to release the vacuum created by the seal, simply pull on the rubber seal tab until you hear a whizzing or hissing sound of air moving quickly. The lid can then be easily removed.
Each jar comes with a glass jar and glass lid, a 100% natural rubber seal, and two stainless steel spring clamps. The jars all have wide openings for clean, easy filling and serving. They are microwave safe (without the clamps and seals). BPA-free, phthalate free, PVC-free, lead-free. Recyclable.