Yes the Sports Card holders work well, but cards tend to slide out when held upside down.
Business Card holders work better and they hold 10 per page horizontally. Business Card holders usually are much more expensive (about 5 for $2) and only seem to be available at office supply stores. I've been able to buy sports card holders at 10 for $1 at some Dollar Stores. They are also available at most Wal-Marts for 10 for $1.98.

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