This is a low-cost; light-weight; high-power rifle scope. I mounted mine on a Barrett M82A1, .50 cal Rifle. No issues with mounting. The scope holds up with the shock of a mighty .50 cal.
I'm a novice with sighting in rifle scopes and it did not take long for me to sight this scope in to 100 yards.
My only issue is with the see-through, yellow, flip-up lens caps. They tend to blur your view at times and the rear lens cap covers the "Fast Focus Eyepiece Design". I had to remove my rear lens cap to adjust the focus on my scope. This should not be a problem if you have the "Rotating Eyepiece Design".
This 10-40x scope has more magnification range than the more expensive
Pros: Light-weight; Two-color Illuminated Reticle
Cons: See-through, Yellow, Flip-up Lens caps
This review was written in the old system and had content requirements that are different than reviews written today.