These cards are from the set of long promide bookmarks by Yamakatsu not sure how many there are in all. The front are prism and they got a regular image on the back. They measure about 6inches tall and 2 wide.

This set is not numbered. Below are the pictures of the packs and the envelopes. The cards are arranged in no particular order.

#1
#1 Back
#2
#2 Back
#3
#3 Back
#4
#4 Back
#5
#5 Back
#6
#6 Back
#7
#7 Back
#8
#8 Back
#9
#9 Back
#10
#10 Back
#11
#11 Back
#12
#12 Back
#13
#13 Back
#14
#14 Back
#15
#15 Back
#16
#16 Back
#17
#17 Back
#18
#18 Back
#19
#19 Back
#20
#20 Back
#21
#21 Back