Able to maintain 29in.-Hg vacuum for over 72 hours at room temperature, they stay gastight allowing reliable storage or experiments over extended periods Viton™ 3-way valve offers consistent and uniform vacuum draw, vacuum release, or gas exchange Transparent polycarbonate construction is durable, easy-to-clean, chemical-resistant, and allows quick visualization of the desiccator contents Amber tinted UV blocking models block 100% of UVA, B, and C light to minimize damages or discoloration of light-sensitive samples Use with any vacuum with free air capacity of 1.5 cubic feet per minute (CFM) ft or greater Single piece molded design (except the door) enables outstanding vacuum capability with virtually no leakage and exceptional durability Cabinet style provides maximum useable space Hinged door allows easy access; built in locking tabs secure the door when not under vacuum Analog vacuum gauge in front door allows vacuum level checking at a glance Perforated shelves can be repositioned to accommodate various storage needs (additional shelves sold separately) Built-in ports permit attachment of up to 3 additional valves (sold separately) Stackable space-saving design allows efficient use of work space Eight models to choose from; 11, 23, 35, and 45 liter internal volume in clear or UV blocking amber