Made with polypropylene thin walls, the 02. mL TempAssure PCR tubes are ideal for laboratory procedures that require quick and uniform heat transfer. This product is free of DNase, RNAse, DNA, PCR, and pyrogen. The tubes can be sealed with the attached flat cap that can be written on for easy sample identification. It comes in a bag of 1000 tubes in various colors of blue, green, red, violet, and yellow.