I use a similar setup with a pill bottle and cotton balls.
These come with there own strings though And when they are soaked in deer urine, they swell up to the point where they don't come out of the film canister easily, therefore perfect for hanging, and then closing again when you leave, until the next time. You can just leave them hanging there closed up, until you return for the next hunt, or pop em back in a plastic bag.
And when they are soaked in deer urine, they swell up to the point where they don't come out of the film canister easily, therefore perfect for hanging, and then closing again when you leave, until the next time. You can just leave them hanging there closed up, until you return for the next hunt, or pop em back in a plastic bag. 
