25W to 120W in line aquarium/pond UV Sterilizers. The Lifegard Aquatics Pro-MAX UV Sterilizer features a patent-pending, flow-through design with less restrictive angled inlet and outlet ports requiring less plumbing. This unique design enables easy installation of new or replacement systems as it can be positioned in multiple ways to fit any tight space. The Amalgam units have a ballast that counts down the number of days until you need to replace the bulb.Related Products:UV Sterilizers by TypeILifegard Aquatics QL & Pro-MAX UV Sterilizer Replacement LampsILifegard Aquatics Pro-MAX UV Sterilizer Replacement Parts.Useful Links:UV Sterilizer OverviewIUV Sterilizer Troubleshooting GuideILifegard Aquatics Pro-MAX UV Sterilizer Instruction Manual.