A watch glass is a circular, slightly convex-concave piece of glass used in chemistry as a surface to evaporate a liquid, to hold solids while being weighed, or as a cover for a beaker. The latter use is generally applied to prevent dust or other particles entering the beaker; the watch glass does not completely seal the beaker, and so gas exchanges still occur.

1. Made of sodalime glass
2. A special process is used that results in an absolutely flat curved surface
3. High clarity, free of bubbles
4. All of them are moulded to the same radius of curvature for convenient stacking

Specification

• Thickness                 1-2 mm
• Material                     Glass
• Shape                       Round
• Temperature             0-200 Deg C