This specification covers common laboratory or filter funnels, and filling or powder funnels for general laboratory use. The laboratory glass funnels shall be classified into four types which are divided into classes. Type 1 is common laboratory funnel with smooth inner surface which is divided into three classes: Class A with short stem, Class B with long stem, and Class C without stem. Type 2 is laboratory funnel with fluted inner wall. The flutes are small grooves or depressions running upward from the bottom zone of the bowl. This type is divided into Class A and Class B. Type 3 is laboratory funnel with ribbed inner wall. The ribs are small raised protuberances from funnel rim toward the stem. Class A and Class B funnels belong to this type. Type 4 is the last type which is filling or powder funnels. This type has short, wide diameter stem.