Sleeves per Page: The options show the pockets per side. If you are looking for 18-pocket albums (9 front + 9 back), select 9-pocket, while for 24-pocket (12 front + 12 back), select 12-pocket.
Inner Sleeve: Inner, tight-fitting sleeve that fits exactly over the card. It is the first step of protection (double-sleeving) before the card is placed in the regular sleeve.
