Kyoka’s Amplifier Jack are two small speakers that Kyoka wears on both her forearms. When she plugs in her Earphone Jack's into the devices, she can amplify even further the sound and vibration of her heartbeat, releasing powerful sonic waves into anything she touches with her wrist amplifiers. The sound waves produced are strong enough to break up the ground. 
Kyoka can remove the sound-amplifying items from her forearms using her Earphone Jack, and aim them towards a specific target, channeling a loud heartbeat.
- ↑ My Hero Academia Manga and Anime: Chapter 99 and Episode 52.
- ↑ My Hero Academia Manga and Anime: Chapter 104 and Episode 54.
- ↑ My Hero Academia Manga: Chapter 208 (p. 8).
|Technology and Other Objects|
|Support Equipment||Air Force Gloves • Amplifier Jack • Artificial Vocal Cords • Capture Tapes • Costume • Electromagnetic Soles • Full Gauntlet • Hydraulic Bracers • High Density Weights • Hover Soles • Iron Soles • Jet Pack • Quirk Amplification Device • Sevens Loud • Sharpshooting Gear • Wire Arrow|
|Weapons||Capturing Weapon • Capture Gun • Cement Gun • Claustro • Curious Flattener • Grenadier Bracers • Hyper-Density Seals • Taser Knuckle|
|Robots||Camera-Bots • Mini Transport Robots • I-Island Security Bots • Villain Bots • Kanidoge's Mechs|
|Substances||Quirk-Destroying Drug • Trigger|
|Literature||Hero Analysis for the Future • Meta Liberation War|
|Miscellanous Objects||Provisional Hero License • Targets|