help identifying a item, please

[loglin2009]

has the letter MCK and picture of a eagle / bird

2 turning knobs / wheels that looks like a car tires

adjustable screw with allen wrench, numbers 0-2, slides on a track, 

do you know what is it, and what is used for?

 

 

 

 

 

 

 

thanks,  tracey

[eburtonlab]

Flip-up sight for a gun or rifle, similar to this one:

https://caagearup.com/product/frs-rear-flip-up-sight/

[loglin2009]

thank you so much, that is exactly what it is, 

can this be sold on ebay? i haven't found any like this one

[eburtonlab]

There are some similar items on eBay, such as this one:

https://www.ebay.com/itm/CAA-USA-MCK-Flip-Back-Up-Sight-MCKRBUS-Set-Black/254459199761?hash=item3b3e...

But unfortunately the fact that someone else has listed one does not necessarily mean that it is allowed by eBay. I am not familiar with the rules regarding weapon sights, and sights are not specifically mentioned in the firearms policy here:

https://www.ebay.com/help/policies/prohibited-restricted-items/firearms-weapons-knives-policy?id=427...