It's so heavy - TRYBE Optics Enhancer Scope Magnification Doubler w/ Tube Mount

Well, my first thought was that maybe it has a couple of D size batteries in there. This unit seems well made but dang it's heavy. I bought it to put on a Leupold Mark 1 1-4x-20 that weighs 8.3 ounces. When I weighed the Trybe Doubler on my digital scale it came out to 8.55 ounces. I hope that means it's very robust. Don't drop it on your toe.