A receiver adapter, straight, with a vacuum connection is a type of laboratory glassware accessory used to connect a receiver flask to a condenser or other glassware component under a vacuum. It consists of a straight tube with a socket at one end that fits onto the neck of the receiver flask and a cone at the other end that fits into the joint of the condenser or other component.

The adapter also includes a vacuum connection, usually a sidearm with a ground glass joint, that allows for the attachment of a vacuum source. The straight design of the adapter allows for a simple and direct connection between the glassware components, making it easier to access and manipulate the components. The receiver adapter, straight, with a vacuum connection is commonly used in chemical experiments where a vacuum is needed, especially in the areas of distillation and reflux.

The adapter ensures a tight seal between the glassware components, minimizing the risk of leakage or contamination during the experiment, while the vacuum connection allows the application of a vacuum source to the setup. This enables the safe and controlled transfer of liquids or gases under reduced pressure, making it ideal for a variety of laboratory experiments.