That's just a bulb...there's nothing special about that price. Appears to be some cheap chinese POS.
BigBlock Reviewed by BigBlock on . Metal Halide - too good to be true? Is this too good to be true? A 400w metal halide for a tenner? http://cgi.ebay.co.uk/NEW-Hydroponics-Halide-Grow-Lamp-Bulb-Light-400watt_W0QQitemZ7743459624QQcategoryZ43555QQrdZ1QQcmdZViewItem Edit: Hes got 600w MH for £11.50 Rating: 5