Box Quantity: 1. Length: 110 mm Width: 70 mm Depth: 30 mm. Power: Volts: 240 Hz: 50. Connections / Fixings: Usually screws to an upright. How it works: Usually activates during a pre-programmed filter cycle or on a 24hr circulation or when in Ozone mode. The Corona Discharge mechanism kicks in and charges the oxygen with Ozone which enters the tub and in turn, helps to kill bacteria with the aid of the sanitizer in the water. Air is drawn through the Ozone on a venturi system and water will pass through the jet sucking in air through the Ozone injector which will be connected to the Ozone. Ozone output is set to 50 mgs/hour. Compatible With: This unit can be fitted to virtually any Hot Tub with a venturi system.