VICTORFIRE High Accuracy Red Laser Boresighter Bore Sighter Kits for .177 .22 to .50 Caliber Rifle Shotgun Factory Set for Ready to Use, No Need to Adjust Screws

The battery case has a small tit on the end and that is what is used for the on/off switch. It keeps the battery from contacting the terminals when it is in a certain position. It works, but was hard to figure out how it works.

Will get close, but ended up buying better boresight

This will get you in the ballpark. You will definitely have to go to the range. This got me on paper at 50 yards but had to do a good bit of adjusting to get center at 100 yards

My Gamo Shadow is now shooting much better after using this gadget. This is the first laser sighter I've used and so far I'm a believer. For the air pellet rifle I didn't even use the end bushing since it seemed to work just fine without. Best to use at dusk or in a dimly lighted shop and it does the job.

The plug securing screw is useless and I had to buy a shotgun cleaning kit to get it out of my ARs barrel. They say to use the suggest fitting plug but I recommend using the second suggest. Even then, no guarantee that you won't be barrel fishing afterwards. Other than that, it is accurate and easy to use.

Though I haven't used it yet it appears to be just what I expected. I think it will do what it is intended for when I put it in service.

Used this to dial in sighting of .177 pellet rifle. Went out to use and could not hit anything.

Not as easy as the instructions insist. It’ll get you on paper close to your target but better off just sighting in the old fashion way.