PentelCOLOR BRSH REFLL WB BLK 2PK

Does this work for pentel fude brush pen xfl2l ?

Does it have the blush, the top or it's just the stick?

Can i use it for pentel fude brush pen, tsumiho (xfl2u)?

I have the pigment pentel brush pen, am i able to switch ink to this one with the pigment pen i have now or do i need to buy a new pen for this ink?