The KYOCERA AVX SCMR18F105PRBA0 is a 1 F supercapacitor from the SCM series, rated at 5.5 V. That 1 F capacitance stores enough energy to hold up a real-time clock or backup a small SRAM for minutes during a power blip — think ride-through for a microcontroller logging data to flash before the rail drops below the brownout threshold. The 250 mOhm ESR at 1 kHz tells you the internal resistance is low enough that the capacitor can deliver a few hundred milliamps of surge current without a big voltage drop — useful when the load wakes up and pulls a pulse from the backup cap. The 0%, +100% tolerance means you get at least 1 F; the actual part could be up to 2 F, so the hold-up time is a range, not a fixed number.
Through-hole radial can — board-fit and thermal budget
Packaged in a radial can with 0.453" (11.50 mm) lead spacing and PC pin termination, it mounts through a pair of holes on a standard PCB. The rated lifetime is 1000 hours at 65 °C. That is the accelerated-life figure — at a cooler 40 °C ambient the actual service life stretches significantly, per the Arrhenius relationship typical for supercapacitors.