The Wheeljack Instant Immobilizer.
The Wheeljack Instant Immobilizer is one of Wheeljack's creations in Animatron. He first immobilized himself in beast mode, but able to speak when not moving. When Megatron and his Predacons took and stole the immobilizer, they immobilized Ironhide in beast mode, among others. A notable victim of the immobilizer is Bluestreak in his platypus mode about to kick. Another notable victim of the immobilizer is Heinrad in his tanuki mode about to attack.
Bluestreak immobilized in platypus mode.
Heinrad immobilized in tanuki mode.
Other victims include Stampy running in rabbit mode, Smokescreen in bear mode about to attack, until Brawn (Beast Wars) managed to reverse the polarization, freeing the Maximals from the immobilization while the freed Ironhide crushes it in elephant mode.
Stampy immobilized in rabbit mode running.
Smokescreen immobilized in bear mode about to attack.
Ironhide immobilized in elephant mode about to attack.