This is a 1:1 scale Borg Arm Weapon Prop Replica.
It is an official and professional prop replica from Roddenberry, who are at the top of the Star Trek props food chain.
It features resin and machined-aluminum parts of the highest quality and comes with a Certificate of Authenticity.
This is a reproduction of the Borg Arm Weapon as seen in the TV series Star Trek: The Next Generation. You can see it in Data’s hands in this image from Star Trek: The Next Generation episode Descent.
Prices vary on this. I’ve seen them on Ebay for as high as $180. But Entertainment Earth have them at the recommended price of $149.99: