Get it wont go wrong - ADE Advanced Optics RD3-009-2 Red Dot Sights

This is great. Comes with a dust cover. Holds zero great as long as you remember to tighten the locking screws. Adjustable brightness. It's awesome. All the reviews saying it doesn't hold zero, didn't read the instructions. Loosen the locking screws, make the windage and elevation adjustments then tighten the locking screws. I've fired about 800 rounds of 9mm NATO after sighting it in and it hasn't moved at all. And yes it comes with the battery and picatinny rail mount so you can mount it on a rail or a pistol.