Glas-Col Hemispherical Mantles Series O Glas-Col Silicone-Impregnated Glass Fabric Exterior. The bottom half of the mantle or neck is left uncovered forming a funnel shape and this is superior to any heating or protecting oven which must conform to a flask exactly or it is not providing an effective seal. The neck ring of the mantle is sealed by a heat-sleeve which prevents heat from escaping at either end and allows access to control the heat by radiation if required. This construction provides an efficient transfer of heat from the source of heat to the appliance or flask. The neck ring of the mantle is an integral part of the mantle; the interior surface of the ring is sealed with heat-sealed tubing. Since the interior of the ring is surrounded by tubing it is unnecessary to have a separate mantle for each neck. There should be nothing between the joint surfaces of the ring and neck ring sealing surfaces. There should be no heat-sealed mantle and neck ring seal. The entire line of Glas-Col heat-sealing mantles are built from the highest quality materials including PTFE quartz and bead-lacquered enamel. These mantles have been tested to withstand 450 C (840 F) internal operating temperature. Specifications for Glas-Col Hemispherical Mantles Series O Glas-Col 100AO408 Silicone-Impregnated Glass Fabric Exterior : For FlaskCapacity mL: 1000 Maximum FlaskDiameter cm (in.): 13 (51/8) Exterior DimensionsO.D. x H cm (in.): 18.1 x 9.7 (71/8 x 37/8) Weightkg (lbs.): 0.64 (1.4) Electrical: 115V 60Hz 380W Glas-Col No.: 100AO408 Unit: Each (1000 ML) (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine Glas-Col products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Laboratory Apparatus with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for Glas-Col Laboratory Apparatus. We are an authorized supplier to all federal and state government agencies as well as to research and educational institutions and can facilitate volume orders on many types of laboratory equipment lab consumables and other products to help fulfill your specific needs. We offer Free Shipping and FREE USPS shipping to APO and FPO addresses on all orders in our store over 49. Please refer to our APO/FPO Shipping and Export Restrictions for more information on export to APO/FPO addresses. In addition to the Glas-Col Hemispherical Mantles Series O Glas-Col Silicone-Impregnated Glass Fabric Exterior 100AO408/ 33787-163 we carry a full complement of Laboratory Apparatus as well as other product offerings from Glas-Col. We also carry a full line of Glas-Col accessories to help meet your laboratory and scientific needs. For a complete selection of Glas-Col Laboratory Apparatus please visit our Glas-Col page. For more brand name Laboratory Apparatus please visit our Laboratory Apparatus store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. Glas-Col Hemispherical Mantles Series O Glas-Col 100AO408 Silicone-Impregnated Glass Fabric Exterior