Made of polypropylene, suitable for both clinical and research applications.They are also free of natural rubber, latex, and heavy metals.High transparency of the material for a clear visualization during experiments specially for molecular biology.Tube and cap designed with the system of flat threads for a complete leakproof.Highly smooth hydrophobic surface for minimum disturbance during centrifugation.Silk-screen blue graduation in the tube and large white frosted portion for easy writing.Autoclavable at 121 ºC, 20 min.Centrifugation resistance: 14.000 xg, except code 429931: 7.000 xg and codes 429950, 429951: 3.500 xgIt is recommended to use adapters to centrifuge and avoid malformations.Available models: 15 ml non-skirted and 50 ml skirted and non-skirted.