This is a ceramic capacitor with part number 1111J1K0P600DQT, characterized by a capacitance of 0.6 pF and a tolerance of ±0.5 pF. It operates at a voltage rating of 1000V (1kV) and features a C0G/NP0 dielectric. The capacitor has a metric package size of 2828, commonly referred to as 1111 in other notations.