Thermo Scientific Nalgene Automatic Self-Zeroing Buret (acrylic) Cat. No. 3640 This Nalgene® buret is individually calibrated and guaranteed to meet accuracy requirements of ASTM E287 Class B. This buret is compatible with most acids and bases commonly used as titrants (except perchloric acid). It is unaffected by dilute mineral acids and bases, except hydrofluoric acid and ammonium hydroxide. The pH range of 1 to 14 is ideal, and up to 5% wt/wt of acids or 30% bases can be used. This buret is not for use with alcohols or other organic solvents. The body of the buret is molded of clear acrylic. While strongly resilient, it may crack or shatter from harsh impact or other abuse. Other components are: • polymethylpentene stopcock housing and tip • low-density polyethylene reservoir bottle with polypropylene closure • 8700 Nalgene 380 (Cat. No. 8007) clear plastic tubing (PVC), three feet • Teflon® TFE stopcock plug: self-lubricating, won’t seize; never needs greasing Cleaning For accuracy in reading, always clean the buret before you use it, including the first time. Use a mild soap or detergent solution. Do not use abrasive cleansers, wire brushes or acid cleaning solutions. You can remove the stopcock plug for easy cleaning by squeezing and slipping off the retaining O-ring. Do not autoclave the buret. Assembly Insert tubing firmly into side flange of buret and through the top of the reservoir bottle, as shown in the drawing. Place cover on top of buret. In order to attach tubing permanently to buret, dip end in methyl ethyl ketone before inserting. Operation Squeeze bottle gently and fill buret just over the zero line. When you release it, excess will return to bottle. For precise self-zeroing, bottle should be at least one-third full. For more information, call Technical Service at the phone numbers listed on the back of this insert.