A cross self-tapping screw, also known as a Phillips self-tapping screw, is a type of screw with a cross-shaped indentation on its head and sharp threads along its length. The screw is designed to create its own threads when driven into a material such as wood, plastic, or metal. This makes it a useful fastener for applications where a pre-drilled hole is not available or desirable.

The cross-shaped indentation on the head of the screw is called a Phillips head, and it is designed to be used with a corresponding screwdriver bit. The Phillips head allows for greater torque to be applied to the screw, reducing the likelihood of the driver slipping out of the head during installation. The sharp threads on the screw allow it to cut into the material as it is being driven, creating a secure and tight fit.

Cross self-tapping screws are commonly used in construction, woodworking, automotive, and electronic applications, as they are quick and easy to install and provide a strong, durable connection.