The Pondmaster Clearguard UV Clarifier Kit adds the benefit of an ultraviolet clarifier to your existing Pondmaster Clearguard Pressurized Pond Filter. UV Clarifiers help control green water and enhance the cleaning action of any Clearguard Pond Filter (maximum of 2 UV Clarifiers can be placed in any Clearguard unit). Features o 9 Watt (15810), 18 Watt (15820) OR 36 Watt (15850) UV Bulb o High-Quality Quartz Sleeve o ETL Listed Transformer with 20' Power Cord