It's the Underworks 998 "The Concealer FTM Chest Binder" aka "The Microfiber Concealer."
Image from Underworks:


What it looks like on an FTM body:


Under a shirt:


Side view:


Side under a shirt:



I'm a 34C, but fairly squishy. I got size XS. I definitely wouldn't recommend this one for a D cup, but if you're C or below and not too perky, it is absolutely perfect. It doesn't roll up at the hips (I wore it for several hours, no rolling), it doesn't bunch up at the waist much if at all, it doesn't create blobs of armpit fat, it's perfectly smooth across the back, there are literally no extra lines anywhere from it, it bends and flexes with your body, and it fits and feels just snug like a tight T-shirt. It has only ever so slightly less compression than the 997, and the other stuff makes it totally worth the slight compression loss because it looks and feels so much more natural.

Oh, and the outer material is a smooth nylon that your shirts won't cling or stick to - it really just feels like an Underarmour-type undershirt from the outside. I think I might almost be able to pass an upper-body grope check.

I have the double front compression shirt and i need another binder maybe Ill shoot for this one

I don't think it would work for my body type.

sleeves too tight

Since I'm anal about how flat my chest is, I have the tri top and I wouldn't think of going with anythign with less than 3 layers of compression cause that's how I am. Even with the tri top, I still worry about my chest not being flat enough. But if it works for you, good on you.

I wish it was affordable

Yeah... I bought that one a couple years ago. Prior to that, all I wore were cotton concealer muscle tees (Underworks). However, they wear out more quickly, so I ended up stuck with the microfiber one. Despite never having had shoulder problems prior, after two months of wearing the microfiber binder, I developed severe bursitis in my right shoulder, to the point that I couldn't even move my right arm without extreme pain. A couple months later, the bursitis switched to the left.

Microfiber binders... they're far too tight. And yes, I had the correct size. But I'd certainly warn anyone who's thinking about buying one that the tiny modicum of extra binding power you'll get might come with a major price for your shoulders, back, or ribs.

SD