This is a deep v-neck undershirt. If you wear your shirt unbuttoned, this is the right style for you. The v-neck is deep enough for you to wear two buttons open without the undershirt being seen.
The fabric is 95% bamboo viscose mixed with 5% elastane for a super-smooth, lightweight material that moves with you. You'll hardly notice you're wearing it. The body is long, so it stays tucked all day.