Hello everyone,
Apologies for asking such a dumb question ( if anyone finds it this way ) , but I got this Align 3-way fuel filter
http://www.align.com.tw/shop/product_info.php?products_id=1759
and couldn't really figure out how this is supposed to work.
One end is connected to the tank, and the other to the engine. I suppose the third is for refuelling.
But then if i refuel using this inlet there are 2 things that will happen;
A. Fuel might go into the engine and flood it.
B. All the debris that was filtered would go back into the tank.

Why is this even needed ? Isnt it easier to just use a simple 2 port filter and disconnect the tanbk line and use it to refuel ?

I just couldn't catch the real use here !

It is used along with a fuel tube clamp from filter to carb to prevent flooding.

Debris will go back to the tank, but I never had so much debris there to consider it an issue.

Hmm, so to fill the tank, one would need to do the following :
1. Remove the clamp from the fill line
2. Remove the line to engine.
3. Clamp the line to the engine.
4. Fill Fuel.
5,6,7 - Do opposite in reverse order ?

Looks like a long list of things to do ! . Why would this be better than just the usual 2 way filter ?

There is no need to remove any line. The clamp can be shut on and off. This is the type I use
http://www.readyheli.com/KSJ9750-KSJ-Fuel-Shutoff-Clamp-Orange-40241_p_34709.html
There are a few more types available.

The fill line has a stopper. The procedure is quite simple. Just clamp on, remove the stopper and fill.

I started with the Align 3 way one, and ended up with the one Rajesh is using now. 

With the Align 3 way one, one has to slide the fuel line (between the filter and the carb) to the narrow part of the fuel clamp.  I found that was some what inconvenient. But that was the only issue, other than that, just remove the fuel intake tube on the middle from clamp, and fill it.  Not too clumsy over all, and serves the purpose well.  Just make sure the inner wire mesh is inserted correctly.