The M1020-2R5305-R from Eaton is a Supercapacitor with Capacitance 3000 mF, Voltage Rating 2.5 to 3.0 V, Equivalent Series Resistance 35 to 50 mOhms, Temperature Operating Range -40 to 60 Degree C. Tags: Through Hole. More details for M1020-2R5305-R can be seen below.