Judging by photos of the jerky dryers on the SmokinTex and Smokin-it sites I'm thinking they use a fan similar to the larger of the two that you have. Pretty hard to tell, looks can be deceiving. Like yours, they are 12 volt. The larger fan may be a tad more robust and better able to handle the hot exhaust and smoke coming from the smoker. Plus, should it not work out well such as moving too much air much too fast, it is easier to shrink down a large housing than stretching a small housing to a larger size. I believe you need a filter between the exhaust port and the fan. Again, just looking at photos. If nothing else, I am sure that some owners of the SI have made their own. You might look through all the posts; use the search bar. And good luck.
Edited by old sarge - 12/21/15 at 5:18pm