The item is described as "a rusty iron sphere that is about three inches in diameter and weighs about a pound. It has a bunch of really strange shapes and designs, almost like it was made from condensed chains that were then melted down into a single sphere. It has a really rough texture on the outside."
Vox Machina looted this item from the bodies of a group of cultists encountered in the Smouldercrown Mountains. It was given to Percy, who programmed it to respond to his own command word. When Percy used the item to restrain a cultist in "Thar Amphala" (1x101), the command word he chose was revealed to be "Manners."