Cyber-sleeve

Cyber-sleeves are mysterious devices bestowed on humans by the Emberstone, forming an empathic bond between the human wearing it and the Transformers the stone also creates. They take the form of a flexible metallic sleeve covering the human's arm and hand, with a light on the back of the hand which glows when an exceptionally powerful emotion is passed on.
Fiction
Earthspark cartoon

When Robby and Mo Malto grabbed the Emberstone, it restrained their hands with green energy which reformed into their cyber-sleeves. Once Twitch and Thrash were created, the two kids quickly realized that the cyber-sleeves were letting them feel the Bots' emotional states. When Robby and Twitch touched their hands together, the interaction caused a blinding light. Secret Legacy, Part 1 Robby was later able to sense through the link when Mo and Thrash were menaced by Arachnamechs. After Twitch and Thrash were abducted by Mandroid, Mo and Robby were able to sense which direction their emotions were coming from, leading the rescue team to Mandroid's base. Secret Legacy, Part 2
Learning that the Terrans had to feel safe and calm to transform, Bumblebee had Robby and Mo help Thrash regain his alternate mode. Moo-ving In While Robby was out looking for his father, Arachnamechs started chasing him with the aim of obtaining his cyber-sleeve. Traditions As Twitch and Thrash's energy began to deplete, their increasing mechanical malfunctions began leaking through the link to Robby and Mo, causing the two kids to physically flail about. The emotions transferring over the link cut off once the two Terrans entered the later stages of energy depletion, until they were able to recharge. Friends and Family After the Emberstone created Hashtag, Jawbreaker and Nightshade, the kids' cyber-sleeve link also extended to the three new Terrans. Age of Evolution, Part 2
Notes
- It's unclear whether they come off.

