A standard ground joint, cone, or single refers to a type of laboratory glassware used for connecting two pieces of glassware together. It consists of a single cone-shaped end with a ground glass surface that fits into a matching socket, forming an airtight seal. The single cone design allows for connection to a single piece of glassware.

This type of joint is commonly used in chemical experiments and is favored for its ease of use and reliability. The single cone joint is a basic design, with one cone end, which is used for simple laboratory setups where a single connection is needed.