These 6-in-1 antennas contain six antenna elements. Typically this means one GPS or GNSS antenna element and five additional element. With six elements, making it possible to offer 2xMIMO or 3xMIMO (Multiple-Input-Multiple-Output) coverage. For example, a 6-in-1 antenna might cover 2xLTE, 3xWiFi and GPS.
There are many different combinations possible. The specific combinations are called out at the product level.