These superior quality unmounted Double Convex Lenses with ground edges are useful for teaching a variety of optical principles.
These Bomex volumetric flasks are fitted with a ground stopper and are accurately calibrated for reliable measuring of liquids and solutions. The neck has a single ring graduation mark. Noted on the flask is the flask's capacity. The glass is clear.
This is pH Test Paper Neutral Litmus, 100 strips per vial. Used to test for acid or alkili.
