Ceramic disc with silver electrode for examing the working condition of LCR meter, impedance analyzer, or piezo meter.

Made with APC 855 (Navy VI) PZT, 5 mm x 5 mm size, 500 um thickness, 

Pack of ten pieces.

Capacitance is around 1.9 nF, dielectric loss is around 2.5%, piezo d33 is around 630 pC/N (well poled)

Curie temperature: 200 C

Heated above Curie temperature may performantly change its dielectric and piezoelectric performance, but can still be used to check the LCR meter with slightly difference capacitance.