Diamond RealSeal Laboratory bottles are precision molded from virgin resins for consistent wall thickness and smooth interior and exterior surfaces. The bottles include leak-proof polypropylene caps that are engineered with an integrated seal ring for leak-proof closure. Caps are linerless to reduce the contamination risk associated with liners. RealSeal bottles and caps employ top quality, semi-buttressed threads with straight shoulders that outperform inferior bottles with round threads. These leak-proof bottles are designed and tested to withstand the highest pressure thresholds in the industry.