70021000

GLASS IN BALLS

70022010

ENAMEL GLASS IN RODS

70022090

OTHR GLS RODS

70023100

TUBES OF FUSED QUARTZ/OTHR FUSED SILICA

70023200

TUBS OF OTHR GLS HAVNG A LINEAR COEFICNT OF EXPNSION NT EXCDNG 5X10 -6 PR KLVN WTHN A TMPRAT

70023900

OTHER GLASS TUBES