The material is slightly thicker and heavier than standard t-shirts as with most polo shirts. It is smooth and comfortable to wear. A little note that it has silver glitter type band around the wrist which is a little difficult to tell from the photos unless you look closely.
In terms of size, I chose size XL based on the shoulder and chest width, but probably would have been better to go down in size to an L as it felt a little baggy.