Shadowless bottom of each tube transmits undistorted light
· Rings and legend are durable white ceramic enamel
· 45310 series is unmatched
· 45310A series is supplied in matched sets of 6. Graduated ring scale of any of the six tubes will not vary by more than 3 mm from that of any other tube within the set
· Manufactured from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements