A retort stand, sometimes called a ring stand, [1] is a piece of scientific equipment, to which clamps can be attached to hold test tubes and other equipment such as burettes which are most often used in titration experiments.
A test tube holder can be made from wood or metal. It is used for holding a test tube in place when the tube is hot or should not be touched. For example, a test tube holder can be used to hold a test tube while it is being heated.