One-Piece tube construction. This reticle is extremely versatile and when properly used will allow the shooter to accurately engage and hit targets at ranges previously thought impossible. Dots are spaced in one mil (milliradian) increments on the crosshair. One useful way to use this reticle is by creating a chart that is based on the size of the object being targeted. By looking through the scope you can bracket the object between dots and refer to the chart for an estimated distance to target. Mueller designed this model with the small caliber target shooter in mind. This scope will focus as close as 15yds. Accurate mil calculations are based off the scope being set at 10 power. When maxed out to 25 power, the actual dot size will cover less than 1/4 of an inch at 100 yds, making it great for longer range hold-over and not having to worry about the dot covering a large portion of the target.