This 25mL Class A burette is made from precisely bored borosilicate 3.3 glass with a PTFE key stopcock and white printed 0.10mL graduations. Class A tolerance is ±0.05mL, conforming to DIN ISO 385 standards. The white graduation markings provide an alternative to blue for applications where white is preferred for visibility against the burette contents. Calibrated for delivery. The borosilicate glass has heat tolerances including a Strain Point of 515°C, Annealing Point of 565°C, and Softening Point of 820°C.