INTERNALLY RIBBED HIGH PURITY ALUMINA RING BAND INSULATOR No.: 118 Outside Diameter: Approximately 3.150”+/- 0.010″ or (80 mm)Inside Diameter: Approximately 2.640”+/- 0.010″ (61 mm)Thickness: Approximately 0.490”+/- 0.005″ (12.45 mm)Rib Thickness: Approximately 0.080”+/- 0.010″ (2.0 mm) You are buying ONE (1) only of an Internally Ribbed High Purity Alumina Ceramic Spacer Ring Insulator. It is in excellent being NOS (New Old Stock). They are made from 98% purity Aluminum Oxide (Al2O3) which of course is Alumina. Generally the balance of composition for this purity Alumina material is of Silicon Dioxide (SiO2) which is Silica. This material has very high hardness, very high stiffness, very good corrosion resistance to chemicals at high temperature, and very high refractory ness or use temperature. They may be used for a variety of electrical, mechanical, and thermal applications. They are great for firing samples in a high temperature kiln. The are great for both industrial or sculptural works of art. They may also be used for jewelry or for applications requiring high wear or abrasion resistance. Your imagination is the only limiting factor in the spectrum of possible applications for this component. Be sure to view all photos as they are an integral component of the item description. The specifications for these components are as follows: Outside Diameter: Approximately 3.150”+/- 0.010″ or (80 mm) Inside Diameter: Approximately 2.640”+/- 0.010″ (61 mm) Thickness: Approximately 0.490”+/- 0.005″ (12.45 mm) Rib Thickness: Approximately 0.080”+/- 0.010″ (2.0 mm) Please Note: There may be slight differences in any or all of the dimensions. There may be firing discolorations. Some may have minor edge chips. These are not precision technical ceramic components. There is no warp or camber Specification for this item. However they are relatively flat. Specific Gravity or Density: 3.9 g/cm3 Water Absorption or Porosity: 0% Fusion Temperature or Melting Temperature: 2000 °C or 3550 °F Maximum Working Temperature: 1700 °C or 3100 °F Thermal Conductivity: 25 W/m* K Specific Heat: 0.9 J/g*K Expansion Coefficient or CTE: 7.5 x 10 E-6 inches/°C Electrical Resistivity at 20 C: 10 E 14 Ohm*cm Electrical resistance at 600 C: 10 E 8 Ohm*cm Modulus of Elasticity: 44 x 10 E 6 p.s.i. or 350 GPa. Normal 0 false false false EN-US X-NONE X-NONE These components were not specifically manufactured for an individual application; therefore be sure to check the dimensional descriptions carefully for your application. Future returns or requests for refunds, because of some “fit” issue or the like will not be honored. Please check the other Alumina component variants that are available in my listings for the model or models that best fits your requirement. Your imagination is the only limiting factor in the spectrum of possible applications for these components and materials. If you require additional technical information, design, or application engineering consultation, feel free to contact us. As a materials scientist with four decades experience in high temperature processing, ceramics, dentistry, and jewelry manufacture it will be possible to provide you with creative and imaginative approaches to your requirements. Feel free to ask any questions you may have regarding this item early. Use PayPal only. Combined shipping discount is provided for multiple item purchases. For best results, please be sure to shop using cart, then complete the paying transaction when you are satisfied that all the items you need are in the cart. Items purchased separately will be shipped separately as a unique transaction. Please complete payment transactions within 3 days. Items are generally shipped via USPS first class mail with delivery confirmation. Ask about shipping costs to your country. Feedback is provided for all buyers. We will appreciate yours as well. We strive to maintain excellent customer service; and are able to solve virtually any issues you may have. Every effort to provide the most accurate information about this item and every appropriate precaution in packaging this item is made, to assure that your highest expectations and satisfaction are met, and are exercised to meet this requirement for excellence. In winning this auction or purchasing this item you are agreeing that you will first provide the seller every opportunity to provide redress or resolution to any issues you many have concerning this item, prior to opening any case about the item or the buyer or leaving any negative feedback about the seller or the item. This is a binding legal transaction. No.: 118 .