[Product Information]

It is a 120V 35Watt E26 screw base led pool light bulb,NOT for 12V,check what you currently have to avoid having to return it.This bulb is able to lit up 25000 gallon pool,and as a bonus burns up a lot less electricity in the process.Works for most Pentair Hayward Light Fixture,no controller need,simply flip the power switch on and off over and over in order to change the light color mode. Please be noted,single red mode only 13 watt,not as bright as blue or other color.
Diameter: 6.69" and High:5.9".Check your fixture before you place order.Direct Replacement Screw Fitting Underwater Pool Light Bulb.COMPATIBILITY: Hayward Astrolite"SP058 Series,Pentair Amerlite 784
Also as others have pointed out, when replacing your old light it's a good idea to put in a new gasket as well. These things don't get changed often and a gasket is not something you want to have fail in this case.
It is a direct replacement bulb (standard screw-in), 35Watt pool led bulb with a lifespan of +65,000 hours. It comes programmed with 16 settings including 7 solid colors and 9 beautiful and unique color "shows".It is the perfect light for medium sized swimming pools and typically used as a replacement for 500w (or lesser) standard lights.