These high-quality vacuum desiccators stay gastight for reliable dry storage or extended experiments, maintaining 29 in.-Hg vacuum for over 72 hours at room temperature.Viton® 3-way valve for consistent vacuum draw, release, or gas exchange; built-in analog vacuum gaugeHigh-quality silicone O-ring and locking ring provide outstanding vacuum capability with virtually no leakageAmber tinted UV blocking models block 100% of UVA, B, and C lightTransparent polycarbonate construction is durable, chemical-resistant, and easy to cleanSix models available; 6, 10, and 20 L internal volume in clear or amber