AIR-CONDITIONING is standard on the Astra convertible, as it is on the SRi, although for the rest of the Astra range it is optional. The single-zone system is manually operated via three rotary dials for temperature, fan speed (there are four speeds) and ventilation direction. Separate buttons are provided for the air-conditioning, recirculation and rear demister functions. The four cabin air vents are equipped with rotary switches, which enable the vents to be closed off, while the dash-mounted demist vents - they direct air onto the side windows when the windscreen demist function is selected - are permanently open. Tinted windows are standard on all Astra models.