The Nikko Stirling Diamond FFP 4-16×44 is a high precision scope with a 30mm main tube. It comes with a reticle in the first focal plane which allows the shooter to make shot corrections with the reticle at any magnification they wish with the corresponding 1/10 mil click value. Also comes with side focus parallax adjustment down to 10m. The Illuminated reticle of the Diamond FFP is red and it has 11 steps to its illumination. The entire reticle of the Nikko Stirling Diamond FFP 4-16×44 illuminates.