The listing, Stamp Mounts has ended.
Each package contains 40 mounts with a dark background.
AH 41/31 Gershwin size
AV 31/41 Legends type commemorative-vertical
C 50/31 Moon landing size-horizontal
E 22/25 For regular issues-vertical
J 40/25 For commemoratives-horizontal
JV 25/40 For commemoratives-vertical
T 25/27 For Chs. of Liberty