Detachable .Green laser sight with independent switch .Easily Control the laser sight The scope is of Red /green reticles with 5 brightness levels；Exit Pupil：3.3mm-10mm；Field of View ...

Find the best telescopes to unlock the wonders of the night sky — just in time for those long winter nights. The best telescope unlocks the wonders of the universe right from your backyard and ...

Metasurfaces offer new possibilities for nonlinear optics, but efficiency is an issue. Researchers have now used DNA-mediated assembly to produce 3D nonlinear optical colloidal crystals whose ...