The Chokebot is a robotic arm developed and constructed by Doctor Krieger at ISIS; it is a powerful mechanical arm, with the strength to crush a billiard ball ("Dial M for Mother"). Dr. Krieger uses it to try to save his relationship with Cheryl who has a fetish for erotic asphyxiation. Krieger however can't choke her hard enough with his "weak woman-y hands."
Doctor Krieger later attempts to sell the Chokebot along with other ISIS equipment and weapons for $41,688 to recoup the lost balance of his ISIS 401(k) ("Jeu Monégasque"). During this transaction, the Chokebot is seen fist-bumping one of the gang members.
The Chokebot is actually just a robotic arm for use in scientific laboratories and other purposes. This one got its name because of its use to satisfy Cheryl's desire for erotic asphyxiation.