Think about newer ATM machines, or credit card readers on a gas pump. You insert your card and pull it right back out without letting go. Same concept here. The bar code is at one end of the ticket. You insert that end into the slot with the bar code facing UP. The code is read and the fastpass ticket immediately spits out from a different slot, which, as PP stated, lacks a tray of any sort to catch the ticket
Instead of pulling the admission ticket back out, stick it in the slot as far as it will go and LET GO. There will be about 3/4" that you were previously holding onto sticking out. Take the second admission ticket and feed it face up right on top of the first ticket. Second fastpass will spit out. Repeat this process until all tickets have been scanned. You will now have a neatly organized stack of park tickets in the slot, that you pull out all at once.
The ticket slot has to be thick to accommodate the plastic type tickets and APs. That's why multiple paper tickets will fit like this. I had 6 tickets which fit just fine. I'm not sure if you can feed more than this, or how many plastic type tickets will fit at once. Hope this helps.
For those needing a visual of the machine, maybe this will help?
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