Magic Tricks

Although there are a few duck tricks available, let's assume that you're asking about "Card Duck" specifically.
It's a 'good' sized duck, but since I don't want to go into storage and get mine to measure it, here's a video of the duck being a duck ;-)
This way...YOU can see it in action and estimate it's size.
If you need exact measurements, you'll have to email PM directly.
It's a fun, silly effect...and it does play well to all groups...just change/modify your presentation to your audience accordingly.
A note for you...most assume that you use playing cards for this. Actually, most do.
However, you can use other types of cards.
Here are two examples:

https://www.youtube.com/watch?v=Xr_vUQH1emM

https://www.youtube.com/watch?v=OviUWXaZJOM

Best wishes...