The shirt says it all.
From the Manufacturer:
You’ve now found the staple t-shirt of your wardrobe. It’s made of a thicker, heavier cotton, but it’s still soft and comfy. And the double stitching on the neckline and sleeves add more durability to what is sure to be a favorite!
• 100% ring-spun cotton
• Sport grey is 90% ring-spun cotton, 10% polyester
• Dark heather is 65% polyester, 35% cotton
• 4.5 oz/y² (153 g/m²)
• Shoulder-to-shoulder taping
• Quarter-turned to avoid crease down the center