["Descriptions:\r\nPowder buffer solution provide long shelf life and stability and are for ideal for low volume use. Each pack makes 250mL of buffer solution. It provides indefinite or long shelf life and stability, for ideal for low volume use. It's lightweight, inexpensive and takes up very little space. These buffers are accurate to within ±0.01pH units @ 25°C and remain stable over long periods of for time.\r\n\r\nPut into solution only what you need, when you need it.\r\n\r\nFeatures:\r\n20 packs of popular pH buffer solutions, 10 packs pH4.01 and 10 packs pH6.86\r\nSimple to use. Just add 250ml per powder packet\r\nPowder has an indefinite shelf life\r\nEasy 3-step procedure is written at the back of the packet\r\n\r\nSpecifications:\r\nEach Pack Volume: 250 ml.\r\nEach powder packet/sachet makes 250ml of solution (when mixed with distilled or deionized water)\r\nAccuracy: ±0.01pH at 25°C\r\nSize: 7.5x6.5cm/2.95x2.56\"\r\nQuantity: 3 Pcs/1 Set\r\n\r\nNote:\r\n1.Transition: 1cm=10mm=0.39inch\r\n2.Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid.\r\n3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!\r\n\r\nNo Retail Package\r\nPackage Contents:\r\n10 x pH4.01 Calibration Powder\r\n10 x pH6.86 Calibration Powder"]