The “X2 Pro” is likely a general designation for various budget in-ear monitors (IEMs) or headphones, as there are multiple models with this name, but generally, they are wired 3.5mm in-ear headphones with a single 12mm or dual dynamic driver, designed for music listening and stage monitoring. Key specifications often found on these models include a 12mm driver, a 16Ω or 32Ω impedance, a sensitivity of around 98dB, a frequency range of 20-20,000 Hz, a 1.2m (or 120cm) cable, and a 3.5mm connector.