PYREX® round glass beaker cover watch glasses are designed to fit PYREX® beakers and all other brands of beakers. They possess high chemical durability, thus preventing contamination of solutions. They are molded to the same radius of curvature for convenient stacking. The heavy wall and uniform fire-polished edge provide mechanical strength. The outside diameter cannot be controlled within close limits and a slight degree of out-of-round can be expected to occur. Material: PYREX® Borosilicate Glass Code 7740. Top Style: Heavy Duty Rim. Available in all diameter sizes ranging from 65mm through 150mm.
PYREX® ribbed watch glass beaker covers are designed for use as covers for PYREX® beakers and all other brands of beakers. Ribs are molded into the glass so that they can't pop off as they do when cane is sealed to standard watch glasses. These glass beaker covers permit the escape of excess vapor and eliminate the risk of contamination from dropped hooks or props. Watch glass beaker covers meet EPA requirements for methods 3005, 3010, and 3020. Material: PYREX®Borosilicate Glass Code 7740. Glass Style: Ribbed. Top Style: Heavy Duty Rim. Available in diameter sizes of 75mm, 100mm & 125mm.
Dynalon polypropylene plastic watch glasses are provided with a stable base and made of chemically resistant polypropylene. Also useful as a beaker cover. Plastic laboratory watch glass will withstand temperatures up to 120° C.
The Dynalon PTFE plastic watch glass is molded from virgin PTFE and has a machine finish to give a smooth surface for ease of cleaning and to eliminate contamination. PTFE plastic watch glass is virtually immune to chemical attack, only attacked by some fluorine containing compounds at high temperature and molten alkalis metals. Working temperature range is from cryogenic to 260°C. Watch glasses are ideal for use as a beaker cover as well.