This Burette Has A Transparent Acrylic Pipe And A Leak-Proof Tpx Stopcock Fitted With A Self-Lubricating Ptee Plug. Each Burette Is Individually Calibrated To Give Maximum Accuracy. Acrylic Body Is Unaffacted By Dilute Mineral Acids & Bases Except Hydrofloric Acid & Ammonium Hydroxide. The Ph Range 1-14 Is Ideal And Can Be Used Upto 5% Wt/Wt Of Acids Or 30% Bases.