help fuel filter question

[2stroke]

I am looking to replace my fuel filter seperator with the following BF1222SP or WIX33617 are there any other brands the same? While I am on this the water sensor port does it include the water sensor or must you use the original one off the bottom cap? One more question my original bottom cap has a schrader in it, is this unusal, whats it used for, the drain is right next to it?

Thanks guys