PELCO MICA DISK,20MM,V1,PKG/10

AFM Mica Discs

Highest quality grade V1 mica, 0.21mm (0.0085”) thick. Interleaved, in packages of 10. Can be mounted on AFM/STM discs.
Available in four diameters:
10mm (0.39")
12mm (0.47")
15mm (0.59")
20mm (0.79")

http://www.tedpella.com/Vacuum_html/Mica_Grade_V1_Properties.htm