Ends can be sealed by flame, sealing clay or patented caps. Manufactured from high quality borosilicate glass. Tubes are packed in plastic vials with re-closeable snap-lock caps to maintain cleanliness Length: 75mm. Inner diameter: 1.1 to 1.2mm. Wall: 0.2mm ±0.02mm. 100 Tubes per vial. Set includes 100 heparinized and 100 plain capillary tubes.