I agree 100% with Jimmie and Pruson on the less is better plan. Here in Alaska, voles and mice are the most common meal for Fox, so I use the vole/mouse sounds. Lip squeaks are great and if you've mastered them, that's all you'll need if you can get into the stand stealthy. The bird distress (woodpecker, starling, chickadee) and snowshoe hare all work too, but vole/mouse is the Fox go-to for me. Sceery AP-6 but the Stewart PC-3 for the deeper, raspier snowshoes, I can't get the AP-6 to go deep enough, but still an awesome call. I just picked up a new open double reed THO custom that will go from mouse squeaks to the raspiest snowshoe I've heard.