PART NO.  SPL.PAGE  DESCRIPTION                                                            
AFH2591   ST.17     Windshield -full width (aluminim and Perspex) -(racing and competition
    equipment, special tuning, Tourer)

The Competition Sports Screen windshield made by Auster was a factory option for MGA roadster models. The key word here is "Sports", as in competition or racing. Notice how low the glass is, only about 6-inches tall. Purpose of this screen is for aerodynamics, to direct air flow over the top of the cockpit. To drive with this setup you will need (minimally) goggles to keep the bugs out of your eyes. Factory part number for this option is AFH2591, which was priced at $65-USD in 1960.

More info at: AT-109, WT-201