Using a clean cloth to hold the lamp, screw the lamp into the E40 bulb-holder fitting of your Pro HPS 400 Volt / 600 Watt reflector until it will turn no further. It is important that the lamp is screwed very firmly into the holder. Failure to fit the lamp tightly will cause arcing inside the holder between the centre connector and the contact on the lamp. This will melt the solder contact on the lamp and irreparably damage it. Ensure the lamp is completely clean and free of dirt, grease and finger-prints etc. before switching it on.
WARNING 1: Once the lamp is switched on it runs extremely hot. As with all high pressure sodium and metal halide bulbs it is necessary to avoid touching the lamp with anything such as fingers or plants as this may cause severe burns or fires. In particular avoid sprays or liquids coming into contact with the lamp as this may cause premature failure or even an explosion.
WARNING 2: This lamp MUST ONLY be used in a a 400 volt / 600 watt system. If it is used in other types of lighting system, then it will either not work or could cause explosions, fire or damage to equipment