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Airtight system: double lock valve locks in air in two ways Internal coil structure Durable PVC PVC Thickness: Single: 0.33 mm / Double: 0.35 mm Flocked PVC on top: single: 0.53 mm / double 0.55 mm
Airtight system: double lock valve locks in air in two ways Internal coil structure Durable PVC PVC Thickness: Single: 0.33 mm / Double: 0.35 mm Flocked PVC on top: single: 0.53 mm / double 0.55 mm