The X-Headphones are headphones originally given to Tsuna by Giannini that allow him to contact the Vongola headquarters, the other guardians, and also lets Reborn make a projection of himself to contact and see Tsuna. They were upgraded by Spanner to connect to the Contact Lenses and voices the amount of Fiamma Voltage Tsuna has for the X-Burner.
Present set[]
A newer version of X-Headphones were created by the present-day Spanner and were sent to Tsuna via Shoichi Irie. According to Shoichi, Spanner created those headphones based on the ones from the Future. These headphones seem to have the same function as the original headphones and contacts, except now Tsuna can use them for Operation XX to activate the XX-Burner .