NYX says: Reduce the look of your pores with our Pore Filler. The perfect pre-foundation basecoat, this talc-free, oil-free formulation includes Vitamin E to smooth and enhance your skin.
The packaging is a nicely functional white squeeze tube.
It has a mousse-like texture and a light tint that disappears when blended into the skin, and it is fragrance-free.
Pore Filler can be used as a primer, on it's own, or even patted over makeup. I find it works best under makeup.
It feels light-weight on the skin, and has the silky slippery application of a silicone-based primer. It does mattify the skin, and keeps oil at bay for a few hours when I wear it on its own (at least in the winter -- it's probably a different story in the summer).
I think this works very well to minimize the look of pores. Obviously, it doesn't treat enlarged pores (a good salicylic acid product or retinoid does that), nor does it truly fill them in completely (the texture isn't thick enough), but it blurs them beautifully both on its own and under foundation. I have rather large pores on my nose, and they look significantly smaller when I use this. I usually only use this on my nose, a little on the cheeks next to my nose, and a little on my forehead.
This seems fairly similar to Benefit's POREfessional, but POREfessional is creamier when coming out of the tube, and it is highly fragranced. If you like the results from POREfessional, I think you would like Pore Filler (and much prefer the price!). They don't look like exact dupes when coming out of the tube, but they feel and wear the same once blended into the skin.
I can definitely tell a difference in the way my base (foundation or tinted moisturizer) applies, wears, and looks when I use Pore Filler. Foundation doesn't pool in the pores on my cheeks, and my nose and forehead look much smoother.
NYX's Pore Filler is $14 USD.