Super soft, comfy material. Like others have said PI runs smaller- I normally wear a small in other brands. I ordered a medium due to the reviews. I'm 5' 7"ish and 145 lbs. The Medium is a bit big on me. Not huge, but slightly loose, not a snug fit like in the product pictures. It's not big enough to send back, but I'd say these jerseys run pretty true to size if you want a snug fit, which is what I want in a cycling jersey anyway. If you are large chested it might make a difference-but I'm not, so a small would have worked fine.I love this jersey! Great fit- very comfortable. I read several reviews and decided on the small. I'm 5'5", 128 lbs and I'll be able to comfortably wear a layer underneath for the cold if needed, but fits great on its own and is comfortable to ride in. Washed well in cold water and hung dry. Will order in another color - highly recommend!Pearl Izumi has yet to disappoint me. This jersey is comfortable and light, perfect for humid summer rides. I ordered a Large based on a previous jersey and this one seemed to run larger, but not enough to have to exchange it.Being right between a small and medium I went with the medium and it fits great. Has just enough room to wear a long sleeve warm shit under it now that fall is here and the mornings are very crisp. The back pockets are handy.The full zipper is nice. The pockets are roomy. The shoulders are just a little wide which it great when your riding or exercising. It runs a 1/2 size smaller than you'd expect. It's contoured- you'll need a reasonable waist size to go with it. It feels silky to wear, better than the wicking fabric. But I don't know what this shirt is like to sweat in just yet.Decent shirt, but the fabric is very, very thin. I've owned a lot of cycling jerseys, never one as thin as this. It's almost delicate. A little bit see-through in fact. Color is otherwise nice. I'll wear it to spin class but probably not outside.I found the material a little heavy for scorching hot tropical summer days. However, if that isn't what you are cycling in, I can highly recommend this. Lovely cut. Fit true to size.A really lovely jersey, but it was a little bit too big. I am 164cm and 65kg. I ordered a large and returned it to Koo bikes (a month ago) asking to swap it for a medium. I have not heard from them at all. A little sad that I may have lost my money on this one.