HOLLOW SQUARE CAPILLARIES MANUFACTURED IN BOROSILICATE GLASS, Square ID: 0.40 x 0.40mm, Wall thickness 0.20mm +/-20%, ID Tolerances +/- 10%, Supplied in plastic vials - Each vial contains 25 capillaries. Available in 50mm, 100mm, 300mm and 600mm lengths. Part numbers 8240-050 (8240-50), 8240-100, 8240-300, 8240-600, ST8240.