Item Description: RGM-700 Portable Gemological Refractometer w/ a 3.6ml Vial of 1.800RI Fluid Comes with instructions! Written by our staff, not converted from another language! Comes with a Gemstone Refractive Index Chart! Comes in a black zipper case! Comes with 3.6ml of 1.800 Refractive Index Fluid - MORE THAN ANY OTHER SELLER! Product Specs: Range: 1.30-1.81 Refractive Index (RI) Resolution: +/- 0.01 RI Accuracy: +/- 0.01 RI Dimension: 4.5" x 1.5" x 2.5" Weight: 400 Grams Sturdy, Portable Design made of die cast aluminum, not plastic like the GIA ones Perfect for the GIAStudent, Hobbyist AND Professional! This item is an exceptional Value! Quality Unit, Right RI Fluid! One BRAND NEW RGM-700 Portable Gemological Refractometer in a Black Vinyl Zipper Case in a sturdy hardcase. This handy little piece of equipment tests a gemstone's ability to slow down or bend light. The amount of slowing down it does to a beam of light is called the refractive index. THIS UNIT WILL HELP YOU DETERMINE WHICH GEMS ARE REAL AND WHICH ONES ARE FAKES! THIS UNIT HAS IT'S OWN INTERNAL LIGHT SOURCE! NO FLASHLIGHT! This unit is helpful in Testing for Cabochons, as well as, testing for Double Refraction! How does it work?: The refractometer works by the use of a glass hemicylinder inside that has a flat surface extending into the body of the refractometer. When light is introduced into the back of the unit, it travel through the glass hemicylinder and up to the gemstone, where the stone is in optical contact with the glass by use of a refractive index liquid. This liquid keeps air from between the stone and the glass hemicylinder and allows light to travel at the same speed through the glass, gets refracted by the gemstone, and then back through the glass hemicylinder to the viewing lens. The amount of slowing down or bending of the light that the gemstone does to the light beam, causes a light and dark area joined by a thin green line. This green line is the refractive index reading of the gemstone. Competitively Priced! This type of unit sells for $595.00 and up at most retailers. Get yours today at Wholesale prices! Included are: * Black Vinyl Softcase * Polarizing Filter * Monochromatic Light Filter * Internal light - Standard wavelength 589nm - runs off 1.5 volt button cell batteries (included) * 3.6ml Vial of 1.800 Refractive Index Oil725RI Fluid - A HUGE GAP THAT RENDERS YOUR RESULTS FLAWED!) ----No One else does this for new units! * Users Guide, BEGINNERS HOW-TO Guide EXTRA FLUID: Add a 10 Gram vial (about 2.5ml) of 1.81 RI Fluid for an additional $59.99. S H is FREE when shipped with your Refractometer! We have several sizes to choose from! Several Refractive Index values too! Check out our store at www.nisupply.com! High Quality! The RGM-700 comes with a 5 year warranty against any defects, so you can buy with total confidence. This unit is made of die cast aluminum and has a smooth finish. It is not made of plastic like the $600 units out there! A deal is only a good deal if the quality is excellent and the seller is still around after the sale for any questions you may have! For LARGER ORDERS, please check out our Store! --- click the tag! International Clients: We ship packages via US Postal's Global Priority Mail/Air Mail for $15.00 ($12.00 to Canada). It takes about 3-8 business days arrive (please note that there can be Customs delays from time to time). Questions? Larger orders? Please e-mail us! DO YOU NEED MORE EQUIPMENT? CHECK OUT STORE AT WWW.NISUPPLY.COM FOR EVERYTHING THE GEM ENTHUSIAST NEEDS! For inquiries about this product, please contact me at the e-mail address below. National Industrial Supply 30777 Rancho California #891420 Temecula, CA 92589, USA Sales: 951.308.9269 Fax: 310.833.7306 We prefer Paypal! We accept Cardit Cards via phone, fax or e-mail too!! Froo www.froo.com | Froo Cross Sell, Free Cross Sell, Cross promote, Marketing, listing Apps, Apps, Application After purchasing, pay instantly with your credit card through PayPal!